Landsmøte 2018 Abstracts

Starting my first research in inorganic chemistry, I stumbled across hydrogen where and when I and everyone else did not expect to find it – it is so common and yet so un-common. It makes bonds more different than any other element – polar and purely covalent as protons and atoms, metallic when it pleases, and ionic as hydride ions. Consequently, it shows up in very different forms and locations and has taken me for a journey to my roots in physical chemistry and to electrochemistry – some things discovered and some mysteries remaining. Hydrogen holds a historical role in the establishment of major Norwegian industry, and we today host world-leading production of electrolyzers for the emerging markets of hydrogen for storage and as carrier of renewable electrical energy.

Many different types of solids contain or may take up water and become solid-state proton conductors by various mechanisms of transport. They may be used as electrolytes in novel types of fuel cells and electrolyzers for hydrogen and renewable energy, as well as in electrocatalytic reactors for upgrading natural gas to liquids or hydrogen with minimal carbon emissions or with carbon capture and storage. The research involves experimental and ab initio computational methods to understand hydrogen in its various forms from gas phase, via surfaces and charge transfer at electrode interfaces, into mobile ions in crystalline or liquid-like condensed phases.

FE1

Bottom-up Assembly of Active, Autonomous and Complex Bioinspired Systems with Adaptive Behaviour

Daniela Wilson

Systems Chemistry, Radboud University Nijmegen, Institute for Molecules and Materials Nijmegen, The Netherlands
d.wilson@science.ru.nl

Self-powered artificial motile systems are currently attracting increased interest as mimics of biological motors but also as potential components of nanomachinery, robotics, and sensing devices [1]. We have recently demonstrated a supramolecular approach to design synthetic nanomotors using self-assembly of amphiphilic block copolymers into polymersomes and the controlled folding of the vesicles under osmotic stress into a bowl shape morphology [2]. The folding process can be precisely controlled to generate different complex architectures [3] with adjustable openings and selective entrapment of inorganic catalysts [4,5] enzymes or multiple enzymes working together in a metabolic pathway [6,7]. Control of the speed and behaviour of the nanomotors is possible due to integration of regulatory feedback and feedforward loops in the enzyme networks designed to preserve energy and run the motors at even lower concentrations of fuel eg. 0.05 mM Glucose. Movement in both blood serum and plasma at physiological concentrations of substrates is consequently demonstrated. The nanomotor is now not only running at low concentrations of fuel but also able to regulate it's fuel consumption to achieve the same output speed showing adaptive behaviour. Recent developments on greater control over the movement of the nanomotors under chemical gradients or temperature will be presented [4,7]. Additional manipulation of the nanomotors under external stimuli and their biomedical applications will be discussed [6,7].

Acknowledgement

This work was supported in part by the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-20012)/ERC-StG 307679 (StomaMotors).

References

a) Abdelmohsen, L. K. E. A., Peng, F., Tu, Y. Wilson, D. A., J. Mater. Chem. B., 2014, 2, 2395-2408. (b) Tu, Y. Peng, F. Adawy, A. Men, Y.; Abdelmohsen, L.K.E.A.; Wilson, D. A. Chem. Rev. 2016, doi: 10.1021/acs.chemrev.5b00344 c) Fei Peng, Yingfeng Tu, Daniela A. Wilson Chem. Soc. Rev. 2017, DOI: 10.1039/C6CS00885B
(a) Wilson, D.A., Nolte, R, J. M., van Hest, J.C.M. Nature Chem. 2012, 4, 268-274. b) Wilson, D.A., Nolte, R, J. M., van Hest, J.C.M. J. Am. Chem. Soc., 134, 9894, (2012). (b) Wilson, D.A., de Nijs, B., van Blaaderen, A., Nolte, R, J. M., van Hest, J.C.M., Nanoscale, 2013, 5, 1315.
(a) R.S.M. Rikken, H. Engelkamp, R.J.M. Nolte, J.C. Maan, J.C.M. van Hest, D.A. Wilson& P.C.M. Christianen "Shaping polymersomes into predictable morphologies via out-of-equilibrium self-assembly", Nat. Commun 2016, doi:10.1038/NCOMMS12606 (b) Fei Peng, Nannan Deng, Yingfeng Tu, Jan C.M. van Hest, Daniela A. Wilson, Nanoscale 2017 DOI: 10.1039/C7NR00142H (b)
a) Abdelmohsen, L. K. E. A., Nijemeisland, M, Pawar, G. M. Janssen, G.-J. A. Nolte, R. J. M., van Hest, J. C. M. & Wilson, D.A. *, ACS Nano, 2016, 10 (2), pp 2652-2660. b) Peng, F. Tu, Y. Pierson, L., van Hest, J. C. M., Wilson, D. A.*, Angew. Chem. Int. Ed. 2015, 54 (40) 11662-11665
a) R. Rikken, R.J.M. Nolte, J.C. Maan, J.C M van Hest, D. A. Wilson P.C.M. Christianen, Soft Matter, 2013, DOI: 10.1039/C3SM52294F R. Rikken, R.J.M. Nolte, J.C. Maan, J.C M van Hest, P.C.M. Christianen, D. A. Wilson Chem Commun, 2013, DOI:10.1039/C3CC47483F
a) Rhee, P. G.; Rikken, R. S.; Nolte, R. J. M., Maan, J. C., van Hest, J. C. M., Christianen, P. C. M. and Wilson, D. A.* Nature Commun. 5, 2014, doi: 10.1038/ncomms6010. b) Fei Peng, Yingfeng Tu, Jan C.M. van Hest, Wilson, D. A.*, Adv. Mater., 2016, DOI: 10.1002/adma.201604996.
(a) Yingfeng Tu, Fei Peng, Xiaofeng Sui, Paul White, Jan C.M. van Hest, Wilson, D. A. Nature. Chem. 2017 DOI: 10.1038/nchem.2674. (b) Yingfeng Tu, Fei Peng, Alain Andre, Yongjun Men, Daniela A. Wilson*, ACS Nano 2017, DOI:10.1021/acsnano.6b08079 (c) Fei Peng, Yingfeng Tu, Ashish Adhikari, Jordi J.C.J Hintzen, Dennis Lowik, Daniela A. Wilson* Chem Commun 2017, 53, 1088-1091. (d) Fei Peng, Yongjun Men, Yingfeng Tu, Daniela A. Wilson, Adv. Funct. Mater. 2018, 10.1002/adfm.201706117 (e) Yingfeng Tu, Fei Peng, Paul B. White, Daniela A. Wilson, Angew. Chem. Int. Ed. 2017, doi: 10.1002/anie.201703276, 56 (26), 7620-7624

FE2

Molecular Assemblers, Molecular Machines Performing Synthesis

R. Herges

Otto-Diels Institute for Organic Chemistry, University of Kiel, Germany

In chemical synthesis usually the reactants are dissolved in an organic solvent, the reactive molecules undergo stochastic collisions and form a bond if kinetic energy and relative orientation are favourable. However, the majority of biologically active molecules in nature are synthesized in ATP driven, molecular machine-type enzyme complexes such as non-ribosomal peptide synthetases (NRPS) or polyketide synthases (PKS). They operate like an assembly line by guiding reactions under positioning control driven by ATP. Notwithstanding the fact that there are a number of advantages to this assembler-like synthesis (less side reactions, easy stereo control, no protecting groups, preselection of reactants, driving unfavourable reactions…), there is no artificial system published so far.

We are aiming at the design, synthesis and investigation of the first model system of a molecular assembler. In our preliminary work we designed and synthesized a light-switchable ditopic receptor which is able to drive the condensation of 4 molecules of vanadate to a cyclic tetravanadate. The reaction which is endergonic and therefore not spontaneous in the absence of the ligand is driven by the large and selective binding energy of the product tetravanadate inside the receptor. Photochemical isomerization (365 nm) of the ligand releases the product. Upon irradiation with 430 nm the original, “empty” state is restored and the cycle starts again.

FE3

Industry lecture

Radionuclides and cancer treatment: How to succeed

Roy Larsen

Oncoinvent AS

Radionuclides have been used for cancer treatment for almost a century. Initially gamma and beta emitters were used but later alpha emitters attracted a substantial attention. Criterion for successful product development should be determined before initiation of the clinical phase of product development. The product candidate’s chemical and physical properties must be carefully considered, and synthesis route should be adaptable to industrial scale. The product candidate must show consistent antitumor activity and acceptable safety profile in the preclinical tests and dosimetry estimates for human use should indicate appropriate benefit to risk ratio. Sufficient patent protection is needed to attract investors.

Radionuclides and properties are addressed, and examples of clinical products are presented.

Norwegian inventions in the field are presented and the international trends in the field are discussed.

FE4

Integrating cryogenic ion chemistry and spectroscopy: Capture and characterization of reaction intermediates in homogeneous catalysis

Mark Johnson

Yale Univerisity

The coupling between ambient ionization sources, developed for mass spectrometric analysis of biomolecules, and cryogenic ion processing, originally designed to study astrochemistry, creates a new and general way to capture transient chemical species and elucidate their structures with optical spectroscopies. Advances in non-linear optics over the past decade allow single-investigator, table top lasers to access radiation from 550 cm^-1 in the infrared to the vacuum ultraviolet. When spectra are acquired using predissociation of weakly bound rare gas "tags", the resulting patterns are equivalent to absorption spectra and correspond to target ions at temperatures below 10K. Taken together, what emerges is a new and powerful structural component to traditional mass spectrometric analysis. Recent applications ranging from the mechanisms of small molecule activation by homogeneous catalysts to the microscopic mechanics underlying the Grotthuss proton relay mechanism in water emphasize the generality and utility of the methods in contemporary chemistry.

FE5

Semi-artificial Photosynthesis

Erwin Reisner

Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
E-mail: reisner@ch.cam.ac.uk
Web: http://www-reisner.ch.cam.ac.uk/

In photosynthesis, light is used for the production of chemical energy carriers to fuel biological activity and the water oxidation enzyme Photosystem II is the first protein complex in the light-dependent reactions of oxygenic photosynthesis. This presentation will summarise our progress in the development of protein film photoelectrochemistry as a technique for the activity of this enzyme adsorbed onto an electrode surface to be studied.[1] Materials design enabled us to develop 'tailor-made' 3D electrode scaffolds for optimised integration of the 'wired' enzyme and these investigations yielded valuable insights into Photosystem II function. Examples are the identification of unnatural charge transfer pathways to the electrode and the elucidation of O₂ reduction pathway that short-circuit the known water-oxidation process.[2]

The integration of Photosystem II in a photoelectrochemical circuit has enabled the in vitro re-engineering of natural photosynthetic pathways. We assembled an efficient semi-artificial water splitting cell driven by light through the rational wiring of Photosystem II to a H₂ producing enzyme known as hydrogenase (Figure 1).[3] This hydrogenase displays unique properties for water splitting applications as it displays good H₂ evolution activity, little product (H₂) inhibition and some tolerance towards O₂.[4] The bio-hybrid water splitting cell shows how we can harvest and utilise electrons generated during water oxidation at Photosystem II electrodes for the generation of renewable H₂ with a wired hydrogenase through a direct pathway unavailable to biology. Progress in the assembly of bias-free tandem water splitting cells with wired enzymes and the integration of robust live cyanobacteria in 3D structured electrodes will also be discussed.[5]

Figure 1. Schematic representation of a semi-artificial water splitting system. Water is photo-oxidized and O2 generated at a Photosystem II-containing photoanode and aqueous protons are reduced at a hydrogenase-based cathode. Enzyme-integration was optimised by using a hierarchical ITO architecture.

References

Kato, Zhang, Paul & Reisner, Chem. Soc. Rev., 2014, 43, 6485-6497.
Zhang, Sokol, Paul, Romero, van Grondelle, & Reisner, Nature Chem. Biol., 2016, 12, 1046-1052.
Mersch, Lee, Zhang, Brinkert, Fontecilla-Camps, Rutherford & Reisner J. Am. Chem. Soc., 2015, 137, 8541-8549.
Wombwell, Caputo & Reisner, Acc. Chem. Res., 2015, 48, 2858-2865.
Zhang, Bombelli, Sokol, Fantuzzi, Rutherford, Howe & Reisner, J. Am. Chem. Soc., 2018, 140, 6-9.

AN - Analytisk kjemi

AN1

ISO/IEC 17025:2017 - en oppdatert versjon av verdens mest brukte akkrediteringsstandard som omfatter generelle krav til prøvings- og kalibreringslaboratoriers kompetanse

Oversikt over endringer og likheter sammenlignet med ISO/IEC 17025:2005.

Maarten Aerts

Norsk Akkreditering

Foredraget er rettet mot laboratorie-ansatte som ønsker å lære mer om ISO/IEC 17025:2017 som kompetansestandard. Akkrediteringsansvarlig i Norsk akkreditering, Maarten Aerts, vil gjennomgå den nye oppbyggingen og strukturen av ISO/IEC 17025:2017, forklare hensikten og filosofien bak den nye versjonen, samt gjennomgå noen sentrale kravelementer som er oppdatert siden 2005-versjonen av standarden.

AN2

Validering av metode - Hvorfor, hvordan og når er det nødvendig?

Elin Lovise Folven Gjengedal

Norges miljø- og biovitenskapelige universitet, Fakultet for miljøvitenskap og naturforvaltning, Ås

Hva er bakgrunnen og begrunnelsen for metodevalidering? Eurachem Guiden “The Fitness for Purpose of Analytical Methods – A Laboratory Guide to Method Validation and Related Topics” forklarer hvorfor, hvordan og når validering av en analysemetode er nødvendig [1]. Foredraget vil handle om arbeidet med guiden, hvordan et valideringsstudium bør utføres og hvor mye som skal inngå i arbeidet (validering/verifisering), forklaring på de ulike valideringsparameterne, oppfølging av valideringsstudien og dokumentasjon på analysemetoden.

Figur 1. Metodevalideringsprosessen [1]. Metodevalidering består av et studium hvor ulike valideringsparametere blir vurdert og deretter sammenlignet med analytiske krav. Metodens egnethet bestemmes av hvordan metoden utfører når den utpekte analytikeren bruker det tilgjengelige utstyret/fasilitetene.

Referanser

B. Magnusson and U. Örnemark (eds.) Eurachem Guide: The Fitness for Purpose of Analytical Methods – A Laboratory Guide to Method Validation and Related Topics, (2nd ed. 2014). ISBN 978-91-87461-59-0. Available from http://www.eurachem.org.

AN3

Utfordringer ved bestemmelse av deteksjonsgrenser

Grethe Wibetoe

Kjemisk institutt, Universitetet i Oslo

Ved bestemmelse av analytter i sporkonsentrasjoner er det nødvendig å etablere deteksjonsgrenser (LOD) for analysemetodene. Metodens LOD er kanskje den valideringsparameteren som har vært gjenstand for mest diskusjon gjennom tidene og er vanskeligst å etablere – spesielt for komplekse analysemetoder.

Det er flere tilnærminger til bestemmelse av LOD, men metoden basert på å multiplisere standardavviket til blankprøve med en konstant (LOD = k·S_blank) er etter hvert blitt den mest vanlige og anerkjente metoden - der det er praktisk å anvende den. Metoden er for eksempel beskrevet i Eurachems valideringsguide for analysemetoder fra 2014 [1].

Selv om utrykket for bestemmelse av LOD er enkelt, er det mange spørsmål knyttet til den praktiske gjennomføringen – spesielt for å få en mest mulig realistisk LOD. Rapportering av resultater nær og under LOD er også et tema som trengs å diskuteres.

Presentasjonen vil gi en kort teoretisk bakgrunn for metoden for bestemmelse av LOD, og forskjellige utfordringer for å kunne bestemme en realistisk deteksjonsgrense for analysemetoden vil bli diskutert.

Referanser

B. Magnusson and U. Örnemark (eds.) Eurachem Guide: The Fitness for Purpose of Analytical Methods – A Laboratory Guide to Method Validation and Related Topics, (2nd ed. 2014). ISBN 978-91-87461-59-0. Available from http://www.eurachem.org

AN4

Analytical challenges in Forensic Toxicology

Veronica Horpestad Liane

Division of Laboratory Medicine, Department of Forensic Sciences, Oslo University Hospital

The Department of Forensic Sciences provides scientific based knowledge at a high international level for use in criminal and civil law. At the section for forensic toxicological analytics, biological samples mainly received from the police are analyzed. High quality analytical methods are required for the analysis of pharmaceuticals and drugs of abuse within this discipline as the results may cause legal sanctions.

In this presentation method validation, measurement of uncertainty and safety margins will be focused. Analytical challenges due to development in the pharmaceutical and illicit drug market will also be mentioned.

AN5

Kjemiske våpen – jakten på bevis.

Bent-Tore Røen

Forsvarets Forskningsinstitutt

Kjemiske våpen er innretninger som inneholder giftige kjemikalier, med en mekanisme for å spre kjemikaliene i lufta, for eksempel i form av en bombe. På tross av stor internasjonal oppslutning om forbud mot bruk av kjemiske våpen har giftige kjemikalier den senere tiden blitt brukt i stor skala i Syria og Irak, samt i målrettede attentat mot enkeltpersoner i Malaysia og Storbritannia. Slike hendelser anses som grove brudd på folkeretten da de påfører store lidelser for dem som blir eksponert, ofte med dødelig utfall.

For å overvåke at den siste internasjonale avtalen om forbud mot kjemiske våpen blir respektert (Kjemivåpenkonvensjonen av 1997), ble Organisasjonen for forbud mot kjemiske våpen (OPCW) opprettet. En av oppgavene til OPCW er å føre bevis i tilfeller der kjemiske våpen har blitt brukt, for å kunne stille aktørene til ansvar for sine gjerninger. OPCW gjennomfører inspeksjoner der blant annet bevismateriale blir samlet inn i form av jord, bygningsmaterialer, klær m.m., eller biologisk materiale fra antatt forgiftede personer.

For å kunne etterprøve kjemivåpenkonvensjonen er OPCW avhengig av laboratorier som kan analysere prøvene, og som tilfredsstiller deres krav til kvalitet og kompetanse. I tillegg må laboratoriene kunne håndtere svært giftige kjemikalier på en sikker måte, og ha tilgang til eller være i stand til å syntetisere relevante referansematerialer. Laboratoriene må hvert år også delta i kvalitetstester ved at de mottar prøver med ukjent innhold, der alle relevante kjemikalier må finnes og rapporteres i henhold til gitte kvalitetskrav. OPCW har i dag et tjuetalls designerte laboratorier, og Forsvarets forskningsinstitutts (FFIs) laboratorium på Kjeller er i ferd med å oppnå en slik OPCW-designasjon.

AN6

Pollutants in the Arctic.

Roland Kallenborn¹, Simon Wilson², Lars-Otto Reiersen³

1. Norwegian University of Life Sciences (NMBU), Ås & University Centre in Svalbard (UNIS), Longyearbyen;
2. Arctic Monitoring and Assessment Programme (AMAP), Tromsø;
3. Arctic Knowledge, Tromsø

The current developments and applications of new, highly sensitive trace analytical methods allowed identification and quantification of a still increasing number of contaminants of emerging concern in the Arctic environment (CEAC = contaminants of emerging Arctic concern). The recently published and updated AMAP report on CEACs are an impressive testimony of the wide array of contaminants currently investigated and monitored in the Arctic Environment.

Earlier source elucidation for legacy organic pollutants identified long-range transport as a major pollutant source for the Arctic. However, the thorough investigation of emerging pollutants revealed a more complex picture. For instance, the evaluation of transport pathways, chemical properties and fate modelling revealed that precursor compounds of selected poly- and perfluoralkyl substances (PFAS) are transported into the Arctic and finally transformed into the well known the transformation products (i.e. PFOS and PFOA) found ubiquitously even in Polar regions.

Based on new scientific assessments on compound specific local sources and complex transport pathways, the Arctic Monitoring and Assessment Programme (AMAP) has, thus, expanded the current assessment strategies. A list of more than 300 CEACs is currently discussed for priority screening in the Arctic.

This list includes modern flame retardants (i.e. phosphorous containing FRs), personal care products (cyclic siloxanes), pharmaceuticals, surfactants, food stabilizing chemicals and many more (for comprehensive information see the current AMAP report on contaminants of emerging concern).
Our presentation will illustrate the implications of these new findings for the in-depth environmental research, regional screening, monitoring activities and regulatory strategies not just for the Arctic environment. In addition, the final implementation in regional and even global regulation frameworks will be discussed and elucidated.

The close interdisciplinary linkage between modern environmental chemistry, toxicology, fate modelling on the one side and monitoring, environmental assessment and regulation on the other is considered as mandatory for the balanced pollution regulations in a changing Arctic with potential conflict scenarios between environmental concerns and geopolitical, economic and strategic interests in the region.

AN7

Organ on a chip: analysis of mini-organs for personalized medicine.

Frøydis Sved Skottvoll

Department of Chemistry, University of Oslo

Current preclinical models (e.g. cell culture- and animal models) often provide data of poor predictive value, thus complicating and delaying conclusions on therapeutic interventions. For this reason, recent advances in tissue engineering and microfabrication have contributed to the development of an “Organ on a Chip”, a microfluidic chip constructed with the purpose of better reconstituting the complexity of human tissues and organs [1].

As the “Organ on a Chip” platform allows for both real-time manipulations and functional readouts, the analytical possibilities are numerous [2, 3]. Integrating the chip unit with a highly miniaturized liquid chromatography mass spectrometry system would provide with unprecedented sensitivity.

Even though the “Organ on a Chip” analytical platform is still in its infancy, this microfluidic intervention is predicted to have a game changing impact on drug screening analysis, diagnosis and personalized medicine.

References

Bhatia, S.N. and D.E. Ingber, Microfluidic organs-on-chips. Nature Biotechnology. Vol. 32 (2014) 760-772.
Wikswo, J.P., F. Block, D.E. Cliffel, C.R. Goodwin, C.C. Marasco, D.A. Markov, D.L. McLean, J.A. McLean, J.R. McKenzie, and R.S. Reiserer, Engineering challenges for instrumenting and controlling integrated organ-on-chip systems. IEEE Transactions on Biomedical Engineering. Vol. 60 (2013) 682-690.
van Midwoud, P.M., J. Janssen, M.T. Merema, I.A. de Graaf, G.M. Groothuis, and E. Verpoorte, On-line HPLC analysis system for metabolism and inhibition studies in precision-cut liver slices. Analytical Chemistry. Vol. 83 (2010) 84-91.

AN8

Metabolomics with mass spectrometry: a powerful tool for clinical analyses.

Skogvold HB¹, Sandås EM¹, Østeby A1, Rootwelt H¹, Arnesen CE¹, Wilson SRH², Rønning PO³, Elgstøen KBP¹

1. Oslo University Hospital, Oslo, Norway
2. University of Oslo
3. Oslo Metropolitan University

Reliable analysis of biomarkers is essential for correct diagnosis and monitoring of inborn errors of metabolism (IEMs), as is the topic of this presentation.

We have previously developed an LC-Orbitrap MS method for untargeted metabolomics of dried blood spots (DBS). This method has been substantially improved and simplified using only one DBS punch, extraction with 80% aqueous methanol with formic acid (mix at 700 rpm, 45°C, 45 min). A mobile phase gradient and analysis time of 27.5 min ensures sufficient separation while maintaining good signal intensity (scan range m/z 50-750, resolution 70 000, electrospray 3.5 kV).

The method is included in research protocols and will be used to detect differences between healthy controls and patients with various IEMs to evaluate existing biomarkers and possibly identify new and better ones. For assessment of the DBS method’s sensitivity in detecting metabolic changes, we conducted an experiment with controlled diet and 36 hours of fasting in six healthy volunteers.

Analytical evaluation revealed excellent results (retention time variation 0.2 % and peak area variation 1-5 % for all analytes). The controlled diet experiment showed that fasting induced changes in the metabolome as well as clustering of results in Principal Component Analysis plots from healthy volunteers when changing from a free to a controlled diet. This demonstrates that the DBS-metabolome is significantly affected by diet and that the method developed is suitable to identify metabolic changes.

The DBS metabolomics method showed excellent analytical performance and ability to identify changes in the blood metabolome reflecting altered physiologic states induced by dietary intervention. The method will be used in research to characterize metabolic states and changes in disease, controlled intervention and during normal daily life activities in order to identify better biomarkers for diagnosis and monitoring of patients with IEMs.

AN9

Sporelementer i sjømat og andre marine prøver -Status og utvikling innen analysemetoder.

Veronika Sele

Havforskningsinstituttet

Sporelementer som arsen, kvikksølv og selen finnes i spormengder i miljøet, der sjømat og marine prøver inneholder generelt høyere nivå sammenlignet med terrestriske prøver. For analyser av sporelementer benyttes ofte ICP-MS (induktivt koblet plasma masse spektrometer). Dette instrumentet er svært sensitivt og elementspesifikt, og har vokst frem som et av de mest anvendte instrumentene innen sporelementanalyser. For noen sporelementer finnes det ulike kjemiske former, eller element spesier. Noen spesier, som for eksempel metylkvikksølv og uorganisk arsen er mer giftig enn andre spesier, og det er derfor viktig å ha verktøy for å kunne bestemme disse. For analyser av elementspesier blir ICP-MS koblet til en kromatografisk separasjon som HPLC (høytrykks væskekromatografi) eller GC (gass kromatografi). Elementer og metaller kan også finnes i form av nanopartikler. Analyse av nanopartikler ved bruk av sp-ICP-MS (single particle ICP-MS) har vokst frem som et forskningsfelt de siste åra. I denne presentasjonen vil det fortelles om bakgrunnen for analyser av sporelementer, og om utviklingen og status innen analysemetoder for sporelementer; med fokus på analyse av sjømat og andre marine prøver.

AN10

Measuring with an MC-ICPMS, examples in earth sciences

Cedric Hamelin

Department of Earth Science, UiB

Multi-Collector Inductively Coupled Plasma Mass Spectrometers (MC-ICPMS) are popular research tools in geology, capable of measuring heavy radiogenic isotopes (e.g. Nd, Hf, Pb, U-Th) and lighter stable isotopes (e.g. Si, Cu, S, Fe), in a variety of material (from sediments to igneous rocks). The applications for MC-ICPMS range from geochronology to climate change, as well as large-scale geodynamic. The new generation of these instruments offers a significant improvement in sensitivity and allow for isotopic measurements for reduced sample sizes. In this presentation, we will focus on how the Nu Instrument Plasma 2 is used in the Bergen Geoanalytical Facility.

AN11

Den norske NMR-plattformen – En plattform for dine kjemiske analyser

Jarl Underhaug

Universitetet i Bergen

NMR, eller kjernemagnetisk resonans, er en essensiell teknikk innen kjemisk-, molekylærbiologisk- og medisinsk analyse. Kjemikere bruker blant annet NMR til å kvalitetssikre organiske synteser og til å karakterisere nye forbindelser, mens molekylærbiologier bruker NMR til strukturbestemmelse av proteiner og til å studere interaksjoner med f.eks legemidler. I industrien brukes NMR blant annet til kvalitetssikring av fødevarer. NMR utvikles også til å bli et diagnostisk verktøy innen medisin. Dessverre krever NMR stort og dyrt utstyr.

Den norske NMR-plattformen er en nasjonal infrastrukturplattform finansiert av Forskningsrådet. Hovedformålet med plattformen er å gi forskere, både ved universitetene og i industrien, tilgang til moderne høyfelts NMR-spektrometre, utstyr som ofte er for dyrt for institutter og mindre bedrifter. Plattformen består av tre moderne, kraftige NMR-spektrometre som er plassert ved NTNU, Universitetet i Oslo og Universitetet i Bergen.

Foredraget vil fokusere på NMR generelt, hvilke muligheter den nye plattformen gir og hvordan man kan få tilgang til instrumenteringen. Det blir tatt utgangspunkt i instrumenteringen som finnes ved UiB, men de fleste analysene kan også utføres ved UiO og NTNU.

AN12

Bruk av kjemometriske metoder i analytisk kjemi.

Knut Dyrstad

KD Metrix

The most common multivariate methods used will be shortly presented followed by examples of applied multivariate analysis in the development of various analytical methods and corresponding multivariate / statistical interpretation of analytical output. Relevant software and how to approach chemometrics for a ‘beginner’ will be discussed.

KA - Katalyse

KAi1

Probing Active Species in Catalysis – Application of Advanced X-ray Techniques

Moniek Tromp

Faculty of Science and Engineering, Materials Chemistry — Zernike Institute for Advanced Materials, University of Groningen, The Netherlands
moniek.tromp@rug.nl

Detailed information on the structural and electronic properties of a catalyst or material and how they change during reaction is required to understand their reaction mechanism and performance. An experimental technique that can provide structural as well as electronic analysis and that can be applied in situ/operando and in a time-resolved mode, is X-ray spectroscopy. Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy is powerful in determining the local structure of compounds including amorphous materials and solutions, since long-range order is not required. Combined X-ray Absorption and X-ray Emission spectroscopy (XAS and XES resp.) provides detailed insights in the electronic properties of a material. Detailed information about the materials in their dynamic chemical active environment can thus be obtained and structure/electronic – performance relationships and reaction mechanisms derived. A combination of spectroscopic techniques (e.g. UV-Vis, IR) gives complementary information about the system under investigation.

Over the last years, different approaches have been reported to allow operando time resolved XAS on catalytic systems, mostly solid-gas. Our group has developed stopped-flow methodologies allowing simultaneous time-resolved UV–Vis/XAS experimentation on liquid systems down to the millisecond (ms) time resolution [1]. Low X-ray energy systems (light elements) or for low concentrated systems, longer XAS data acquisition times in fluorescence detection are required and therefore a stopped flow freeze-quench procedure has been developed [2]. Pushing the time-resolution has been achieved by synchronizing the synchrotron bunches with an optical laser in order to perform fast pump-probe experiments [3] or micro-reactors for modulation excitation experiments [4].

Developments in XAS using new instrumentation and data acquisition methods while selecting specific X-ray energies provide this more detailed electronic information [5]. High energy resolution XAS, XES and Resonant Inelastic X-ray Scattering (RIXS) provide very detailed electronic information on the systems under investigation. The secondary spectrometer design also opens up lab based spectrometer designs as will be demonstrated.

The methodologies and instrumentation have been developed and applied to a wealth of materials science, for homogeneous and heterogeneous catalysis to batteries and fuel cells as well as art objects. In this lecture, several examples will be given with an emphasis on homogeneous catalysis, providing insights in activated species and reaction mechanisms of selective oligomerisation reaction.

References

e.g. Tromp M. et al. Organometallics 2010, 29, 3085–3097.
Bartlett S.A. et al. J. Catal. 2011, 284, 247–258; ACS Catalysis 2014, 4, 4201; Catal. Sci. Techn. 2016, 6, 6237; Tromp, M. et al, under review.
Tromp, M. et al. J. Phys. Chem. B 2013, 117(24), 7381–7387.
Tromp, M. manuscript in preparation.
e.g. Thomas, R. J. et al. J. Phys. Chem. C 2015, 119(5), 2419–2426; Tromp M. et al, under review.

KAi2

From Homogeneous to Heterogeneous catalysis: Use of Microporous Solids as Macroligands

Jéróme Canivet

Univ. Lyon, Univ. Claude Bernard Lyon 1, CNRS, IRCELYON - UMR 5256, Villeurbanne, France.
jerome.canivet@ircelyon.univ-lyon1.fr

At the molecular scale, the integration of the catalytically active centers into a solid support without loss of performance compared to the homogeneous analog is still a major challenge. In this context, a molecularly defined support as macroligand, i.e. a solid acting like the ligand in the corresponding molecular complex, can be considered as a key to bridge the gap between molecular and heterogeneous catalysis. Metal-Organic Frameworks and purely organic microporous polymers are promising candidates. In particular, porous frameworks made by the repetition of a coordinating motif, like the bipyridine motif are of a high interest as far as bipyridines are widely used as chelating ligand for molecular catalysts.[1,2]. We show that both homogeneous and heterogenized catalysts follow the same linear correlation between the electronic effect of the ligand, described by the Hammett parameter, and the catalytic activity as exemplified in two reactions. This correlation highlights the crucial impact of the local electronic environment surrounding the active catalytic center over the long-range framework structure of the porous support. The gap between molecular and heterogeneous catalysis has never been so close to being bridged. This work is carried out within the H-CCAT project that has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 720996. H-CCAT aims at the large scale production of MOF catalysts and at their use in the industrial production of pharmaceuticals.

References

F. M. Wisser, P. Berruyer, L. Cardenas, Y. Mohr, E. A. Quadrelli, A. Lesage, D. Farrusseng, J. Canivet, ACS Catal., DOI: 10.1021/acscatal.7b03998 (2018)
F. M. Wisser, Y. Mohr, E. A. Quadrelli, D. Farrusseng, J. Canivet, ChemCatChem, DOI: 10.1002/cctc.201701836 (2018).

KA1

One-step sol-gel synthesis of Cu/Ordered Mesoporous Alumina Powders

Ole Håvik Bjørkedal*, Magnus Rønning

Department of Chemical Engineering, NTNU, Trondheim
*ole.h.bjorkedal@ntnu.no

Ordered Mesoporous Alumina (OMA) may be synthesized by a sol-gel process, using micellular polymers as a template for pore structure [1]. The resulting amorphous alumina powder has narrow pore size distribution and high surface area, and is well suited for use as a catalytic support, e.g. by impregnation. An alternative to impregnation and other similar twostep syntheses is to introduce the metal directly into the sol-gel process via a suitable precursor.

Inspired by Cu/zeolite systems, Cu/OMA materials have been regarded as a potential catalyst for NH3-SCR catalyst. A common way of synthesizing such materials are by two stepmethods such as impregnation of a support. An alternative procedure (illustrated in Figure 1) is to synthesize the catalyst in one step, by introducing the metal precursor directly to the solgel process forming the support structure [2].

One advantage with this procedure is an opportunity to surpass the limitations of metal loading in ion exchanged zeolitic catalysts while obtaining a high dispersion of copper sites on the surface. Cu/OMA materials have also been prepared by incipient wetness impregnation for comparison. Samples were characterized by N2 physisorption, XRD and TPR. In situ XAS studies have also been performed to investigate the materials' behavior under reducing and oxidizing SCR conditions.

Figure 1: Formation of Al2O3 (grey) from Al(OPr)₃ around structure-directing micelles forming regular-sized pores. Copper (blue) is added to the sol.

References

G. S. Armatas, A. P. Katsoulidis, D. E. Petrakis, and P. J. Pomonis, “Synthesis and acidic catalytic properties of ordered mesoporous alumina–tungstophosphoric acid composites,” J. Mater. Chem., 20, 39, 8631 (2010).
G. J. B. Voss et al., “Mesostructured alumina as powders and thin films,” J. Mater. Chem. A, 2, 25, 9727–9735 (2014).

KA2

Methane to methanol conversion over Cu-zeolites – the XAS view

E. Borfecchia¹*, D. K. Pappas¹, M. Dyballa¹, A. Martini^2,3, K. A. Lomachenko⁴, G. Berlier², P. Beato⁵, C. Lamberti^3,6, S. Bordiga^1,2, U. Olsbye¹, S. Svelle¹

Center for Materials Science and Nanotechnology, Dept. of Chemistry, University of Oslo, Oslo, Norway
Dept. of Chemistry and NIS Centre, University of Turin, Turin, Italy
The Smart Materials Research Institute, Rostov-on-Don, Russia
European Synchrotron Radiation Facility, Grenoble, France
Haldor Topsøe A/S, Kgs. Lyngby, Denmark
Dept. of Physics, University of Turin, Turin, Italy

* corresponding author elisa.borfecchia@smn.uio.no

A process allowing energy-effective methane to methanol (MTM) conversion would represent a major breakthrough for chemical industry. Cu-exchanged zeolites have been shown to possess Cu active sites able to cleave the C−H bond of methane at temperatures ≤ 200 °C, enabling its stoichiometric transformation into methanol [1]. The conversion is performed through a stepwise process, involving high-temperature activation in O2 to generate the active sites, methane loading at 200 °C, and steam-assisted methanol extraction.

We have combined laboratory performance testing with in situ/operando Cu K-edge XAS to establish structure-activity relationships for the MTM conversion over Cu-CHA [2] and Cu-MOR [3] zeolites. By operando XAS, we tracked the oxidation state and average coordination of Cu ions during each step of the process and explored the impact of different pretreatments and compositional characteristics by in situ XAS.

High-temperature reaction with O₂ is evidenced as a key requirement to form the Cu(II) active sites (Fig. 1a), which then undergo reversible redox chemistry during the CH₄-loading and CH₃OH extraction steps. For Cu-CHA, we identified a positive linear correlation between the methanol productivity and the composition-dependent self-reducibility under high-temperature treatment in He (Fig. 2b), allowing us to rationalize the composition impact on the productivity for the MTM conversion (Fig. 1c). The most recent research efforts on Cu-MOR have highlighted the crucial role of keeping consistent conditions for spectroscopy and performance testing. Having fulfilled this requirement, aided by high-energy resolution XANES and multivariate analysis [4], we unambiguously assessed the nuclearity of the Cu-active site in the investigated series of Cu-MOR materials. These studies highlights the potential of the combination between XAS and testing at consistent conditions and paves the way for rationalized material synthesis to develop an industrial MTM process.

Figure 1. In situ XAS of (a) Cu-CHA with Cu/Al=0.5, Si/Al=12 after different pre-treatments (inset: corresponding normalized CH3OH productivities); (b) He-activated Cu-CHA with Cu/Al=0.5 and Si/Al ratio of 5, 15 and 29 (inset: linear correlation between the normalized productivity and the fraction of Cu(I) species in the He-activated state. (c) Rationalization of the effect of Cu-CHA composition on the MTM productivity.

References

E. Borfecchia et al., Chem. Soc. Rev. (2018) in press, doi: 10.1039/c8cs00373d.
D. K. Pappas et al., J. Am. Chem. Soc., 139 (2017) 14961.
D. K. Pappas et al., J. Am. Chem. Soc., under review.
A. Martini et al., Chem. Sci. 8 (2017) 6836.

KA3

Low temperature methanol synthesis catalyzed by Copper nanoparticles and alkoxide system

Christian Ahoba-Sam^1,2*, Unni Olsbye¹ and Klaus-Joachim Jens²

1 - Department of Chemistry, University of Oslo, Oslo,2 - Department of Process, Energy and Environmental Technology, University of South-Eastern Norway, Porsgrunn.

* chriaho@kjemi.uio.no

Methanol (MeOH) is identified as a multipurpose molecule, which has a high potential as a C1 building block for both energy and CO2 storage [1]. MeOH synthesis at temperatures below 120 oC in a liquid medium presents the possibility of achieving full syngas conversion per pass [2]. The Low temperature approach is advantageous over the current technology for MeOH production since the former is thermodynamically favourable and gives a high yield per pass. The low temperature methanol synthesis (LTMS) process involves two main steps, (i) MeOH carbonylation to form methyl formate and (ii) hydrogenolysis of methyl formate to form MeOH, illustrated in equations (1) and (2).

𝐶𝑂 + 𝐶𝐻₃𝑂𝐻 ⇆ 𝐶𝐻₃𝑂𝑂𝐶𝐻 (1)

𝐶𝐻₃𝑂𝑂𝐶𝐻 + 2𝐻₂⇆ 2𝐶𝐻₃𝑂𝐻 (2)

Our aim was to characterize, develop and evaluate the LTMS catalyst system. A once-through catalyst system involving copper (II) salt and methoxide was used to obtain up to 92 % conversion (> 94 % selectivity to MeOH) per batch within 2 h at 20 bar syngas pressure and 100 ^oC temperature. XRD and TEM characterization of the slurry catalyst system revealed that about 10 ± 5 nm Cu nanoparticles were involved in the catalytic process [3]. Decreasing Cu nanoparticles sizes led to increased MeOH production due to an increase in active Cu surface area, which enhanced methyl formate hydrogenolysis. Agglomeration of the Cu nanoparticles in the course of MeOH production was identified as a major cause for the deactivation of the Cu nanoparticle component of the LTMS catalyst system. Furthermore, with the aim of investigating the role of solvents polarity on the LTMS, MeOH production maximized for solvents with dielectric constant (ɛ) around 7.2, similar to the polarity of diglyme. A probe of possible side reactions of the main intermediate revealed that, in the presence of methoxide, low polar solvents enhanced decarbonylation of methyl formate while high polar solvents enhanced a nucleophilic substitution to form dimethyl ether and sodium formate.

References

Olah, G. A., Angew. Chem. Int. Ed. 44, (2005), 2636–2639
Christiansen, J. A., (1919), U.S. Patent 1,302,011.
Ahoba-Sam, C., Olsbye, U., and Jens, K.-J., Catal. Today, 299, (2017), 112-119

KA4

Bimetallic Ni-Fe hydrotalcite-derived catalysts for dry reforming of methane

Huong Lan Huynh, Henrik Berg, Dori Kalai, Kristian Stangeland, Zhixin Yu*

Department of Energy and Petroleum Engineering, University of Stavanger, 4036 Stavanger, Norway
* corresponding zhixin.yu@uis.no

1. Introduction

Reducing greenhouse gas emissions is the major concern for most of the world’s leading economies. Amongst proposed technologies, dry reforming of methane (DRM) has become a promising approach since it converts natural gas (CH₄) and carbon dioxide (CO₂) into syngas (H₂ and CO), a valuable building block for fuels and chemicals. However, the development of active and stable catalysts for DRM is still challenging. Transition metals (e.g. Ni, Co) are commonly used due to their good activity but they still suffer from fast deactivation because of carbon deposition and metal sintering. Recently, alloying Ni with other metals has attracted much attention as an alternative catalyst for DRM reaction.

2. Experimental

In this study, a series of bimetallic Ni-Fe catalysts supported on MgAl₂O₄ were prepared via hydrotalcite (HT) precursors. Ni loading was kept constant at 20 wt.% while Fe/Ni molar ratio was varied from 0 to 1. Two different coprecipitation methods were studied, namely conventional method (low supersaturation) and fast injection method (high supersaturation) with and without aging step. The characteristics of catalysts were investigated by X-ray diffraction, nitrogen adsorption-desorption, hydrogen chemisorption, temperature programmed reduction and temperature programmed desorption. DRM reaction was occured at 700 ºC and atmospheric pressure, with equimolar CH₄/CO₂ feed at high gas hourly space velocity.

3. Results and Discussion

Based on XRD data of as-prepared catalysts, the HT-like materials were synthesized by coprecipitation method without impurities and high crystallinity. The structure was fully decomposed to oxides after calcination at 600 ºC. Overall, the catalysts had high BET surface area and pore volume, representing the advantage of using HT precursors for catalyst synthesis. The addition of Fe improved the reducibility and basicity of the catalyst. However, high amount of Fe content did not favor the Ni dispersion, based on hydrogen chemisorption data. In DRM reaction, bimetallic catalysts exhibited better performance than monometallic catalyst. The optimal composition was found at an Fe/Ni molar ratio of 0.1.

As for catalysts synthesized by fast injection (high supersaturation) method, Ni and Fe was successfully incorporated in HT-like structure. The fast-method catalyst (with aging step) had the highest surface area, pore volume, and narrow pore size distribution, indicating a more uniformity in particle size. The reducibility and basicity were also improved. As expected, this catalyst performed the best conversion of reactants and no deactivation was observed during 18h TOS. Spent catalysts were studied by XRD; graphite was detected in all samples; possible Fe3O4 was depicted, supporting the proposed role of Fe to suppress carbon formation by FeO + C -> Fe + CO reaction [1].

4. Conclusions

High supersaturation synthesis could be an effective approach to improve the activity and stability of bimetallic Ni-Fe catalysts for DRM reaction.

References

S. M. Kim et al., "Cooperativity and Dynamics Increase the Performance of NiFe Dry Reforming Catalysts," J. American Chem Soc., 139, 5, 1937-1949 (2017).

KA5

Mesoporous spinel manganese-cobalt oxide catalysts for CO2 hydrogenation to methanol

Kristian Stangeland¹, Dori Yosef Kalai, Zhixin Yu*²

1 – Department of Energy and Petroleum Engineering, University of Stavanger, 4036 Stavanger, Norway
* corresponding Zhixin.yu@uis.no

Conventional copper-based catalysts have been extensively studied for methanol synthesis from CO₂, which generally exhibit insufficient activity and selectivity. Recently, several novel catalytic systems have been reported to be promising for CO2 hydrogenation to methanol (e.g., Ni(Pd)-Ga, Ni-Sn/InZrO₂, In₂O₃/ZrO₂, ZnO-ZrO₂, and MnO_x/Co₃O₄) [1-2]. Cobalt-based catalysts are interesting due to its ability to catalyze different CO₂ hydrogenation reactions to produce methane, methanol, and higher alcohols. It has been shown that the selectivity of cobalt-based catalysts can be tuned through optimizing surface properties by utilizing suitable promoters and supports. Therefore, it will be interesting to identify the nature of the active site and tuning the selectivity of cobalt-based catalysts for CO₂ hydrogenation. In this work, a series of mesoporous manganese-cobalt catalysts with different manganese loading (0, 10, 20, 50, and 100%) were prepared by a modified sol-gel reverse micelle method. The catalyst were characterized by N₂ adorption-desorption, XRD, XPS, ICP-AES, H₂-TPR, CO₂-TPD, and TEM. Catalytic testing was carried out in a continuous flow reactor.

A substantial enhancement in methanol selectivity was observed with the addition of manganese to mesoporous Co₃O₄, which was attributed to a significant enhancement in the surface basicity. The methanol selectivity was found to strongly depend on the reduction temperature, and reducing the catalysts at 250 ºC resulted in the highest methanol selectivity. In contrast, reduction at 200 ºC resulted in an increase in CO selectivity, whereas methane selectivity increased after reduction at 300 ºC. The highest methanol selectivity and methanol formation rate was obtained over the 20MnO_x-Co₃O₄catalyst. The superior performance of 20MnO_x-Co₃O₄ was attributed to enhanced basicity, more easily reducible species, high surface area, and a higher concentration of well-dispersed manganese species at the surface. The lower activity of the 50MnO_x-Co₃O₄ catalysts was attributed to manganese blockage of active cobalt sites. The methane was the majority product over the catalysts regardless of the reaction conditions. Therefore, further effort is necessary to increase the methanol selectivity.

Figure 1. CO₂ conversion and product selectivity (left) and the effect of manganese loading on the methanol formation rate (right) for the Co₃O₄, xMnO_x-Co₃O₄ and MnOx catalysts.

References

Richard AR, Fan M (2017) Low-Pressure Hydrogenation of CO₂ to CH₃OH Using Ni-In-Al/SiO₂ Catalyst Synthesized via a Phyllosilicate Precursor. ACS Catalysis 7 (9):5679-5692
Li C-S, Melaet G, Ralston WT, An K, Brooks C, Ye Y, Liu Y-S, Zhu J, Guo J, Alayoglu S (2015) High-performance hybrid oxide catalyst of manganese and cobalt for low-pressure methanol synthesis. Nature communications 6:6538

KA6

The CO-induced surface reconstruction on Co(11-20)-a combined theoretical and experimental investigation

Hilde J. Venvik¹*, Marie Døvre Strømsheim¹, Ingeborg-Helene Svenum², Mari Helene Farstad¹, Kees-Jan (C.J.) Weststrate³, Anne Borg⁴

- Department of Chemical Engineering, NTNU, 7491 Trondheim, Norway
- SINTEF Industry, 7465 Trondheim, Norway
- SynCat@DIFFER, Syngaschem BV, P.O. Box 6336, 5600 HH Eindhoven, the Netherlands
- Department of Physics, NTNU, 7491 Trondheim, Norway

* hilde.j.venvik@ntnu.no

The surface dynamics of a model Fischer-Tropsch catalyst upon exposure to CO has been investigated with a combination of experimental and theoretical methods. The surface of Co(11-20) was chosen as the model system as it is known to undergo a CO-induced (3x1) surface reconstruction [1,2] which involves the anisotropic migration of Co [2] along [0001], initiating from the step edges.

The restructuring was studied with low energy electron diffraction (LEED), scanning tunnelling microscopy (STM), temperature programmed desorption (TPD), infrared spectroscopy (IR) and DFT. Three theoretical model surfaces with a (3x1) periodicity were selected and are displayed in Figure 1; one unreconstructed surface (a), and two with either a missing row (MR) (b) or an added row (AR) (c) of Co atoms along [0001], to represent the
reconstruction. The calculations were performed with the Vienna ab initio simulations package (VASP) [3].

Figure 1. The calculated preferred adsorption geometries of 4 CO on (3x2) model surfaces of Co(11-20) (a) unreconstructed (b) MR and (c) AR.

Calculations showed a slightly higher stability for CO adsorbed on the reconstructed surfaces than the unreconstructed, with CO in coordination with the added row yielding the lowest calculated adsorption energies. The removal of a Co atom from the topmost layer and its mobility across the surface was investigated through transition state calculations with climbing image nudged elastic band (CI-NEB) [4]. These results as well as effects of coverage will be discussed in relation to the experimental data.

References

H. Papp, Surf. Sci. 149 (1985) 460.
H.J. Venvik, A. Borg, C. Berg, Surf. Sci. 397 (1998) 322.
G. Kresse, J. Hafner, Phys. Rev. B 47 (1993) 558.
G. Henkelman, B.P. Uberuaga, H. Jónsson, J. Chem. Phys. 113 (2000) 9901.

KA7

CO₂ Hydrogenation over Functionalized UiO Zr-MOFs

Emil Sebastian Gutterød, Unni Olsbye*

Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, Sem Sælandsvei 26, N-0315, Oslo, Norway

* corresponding unni.olsbye@kjemi.uio.no

Valorization of CO2 through hydrogenation to products such as CH₄, CO and CH₃OH, is attractive for a less fossil-carbon dependent future [1]. An important research target is tailored catalytic activity and selectivity by carefully designed catalyst systems [2]. Metalorganic frameworks (MOFs) are highly tunable in numerous ways, such as in pore size, in linker functionality and by metal inclusion. In this work, CO₂ hydrogenation was carried out over Pt-functionalized UiO-67 and UiO-67-binaphtalene Zr-MOFs at T = 170-280 ºC, p = 1–8 bar, H₂/CO₂ = 0.2–9 and contact time τ = 0.005–0.04 g cat min/ml [3]. Under all tested conditions, CO was main product of reaction at more than 70% selectivity. The selectivity toward minority products CH₄ and CH₃OH is highly dependent on conditions, as well as the MOF characteristics. Isotope labeling experiments showed that methane is formed from CO₂, via CO. Modification of the MOF with bulky and hydrophobic binaphtalene-type linkers resulted in an increased CO selectivity and Eapp of CH₄ formation. Comparison to Pt/SiO₂ showed very similar activation energy of CO formation, however, the turnover frequency over Pt/SiO₂ was significantly lower, and no significant formation minority products was observed. The Pt containing UiO-67 Zr-MOF catalysts showed stable activity during 60 h of testing.

Figure 1. Selectivity of CO (squares) and CH₄ (circles) versus conversion over UiO-67-Pt (black) and UiO-67-binaphtalene-Pt (blue) during CO₂ hydrogenation at ambient pressure, 240 °C, CO₂/H₂/He = 1/6/3 and τ = 0.005-0.04 g cat min/ml.

References

W. Wang, S. Wang, X. Ma, J. Gong, Chem. Soc. Rev., 2011, 40, 3703–3727.
S. Kattel, P. Liu, J. G. Chen, J. Am. Chem. Soc., 2017, 139, 9739−9754.
E. S. Gutterød et al., Ind. Eng. Chem. Res., 2017, 66, 13206-13218.

KA8

Operando characterization of Pd-functionalized UiO-67 for CO2 hydrogenation reaction

A. Lazzarini¹,*, G. Kaur¹, E. S. Gutterød¹, S. Øien Ødegaard¹, K. P. Lillerud¹, U. Olsbye¹, and S. Bordiga^1,2

1 – Department of Chemistry, University of Oslo, Sem Sælands vei 26, 0371 Oslo, Norway
2 – Department of Chemistry, University of Torino, via G. Quarello 15, 10135 Torino, Italy

*Corresponding author: andrea.lazzarini@smn.uio.no

1. Introduction

Metal-functionalized MOFs are gaining importance in the field of heterogeneous catalysis [1]. In the recent years, our research group focused its efforts on the production of Zr-carboxylate based MOFs, among which, mixed linker UiO-67 materials, represent an interesting example. 10% of bipyridyl-based linker, substituting the classical bpdc linker, allowed the grafting of PtCl₂ moiety on the bipyridyl functionality (Figure 1a) [2a]; thermal reduction in H2 results in the formation of metal nanoparticles encapsulated in the MOF pores [2b]. The obtained material was tested for the CO2 reduction with H2, showing a good selectivity towards CO and excellent stability at operat-ing conditions [3]. Among all the metals investigated up to now, Pd is one of the less explored in the field of MOFs [4], despite its well-known high activity for hydrogenation and reduction reactions in general. In the present study, PdCl₂-functionalised UiO-67 was successfully tested in operando conditions for CO₂ reduction reaction.

2. Experimental

The sample (hereafter Pd-UiO-67-bpy) was obtained following the post-synthetic functionalization (PSF) method described in Ref. [3]. PXRD and surface area analysis were performed to check the structural stability of the material before and after the reaction. SEM microscopy was used to control the shape of the crystals after each step of the process. The material was then activated and tested in operando conditions by means of a combined DRIFT/GC-MS method, able to have a simultaneous control on both the status of the catalyst and the products developed during reaction.

3. Results and discussion

Figure 1b shows the PXRD pattern of the sample before and after Pd impregnation. From that, it is possible to confirm that the MOF maintained its crystallinity. As expected, the surface area slightly decreases after the PSF with PdCl₂, passing from 2618 m²/g to 2398 m²/g (Figure 1b - inset). The catalyst was placed inside a Praying Mantis DRIFT cell for IR measurements and activated in a 10% H₂ flow (10 ml/min) at 300°C for 15h, allowing the formation of Pd NPs inside the pores of the MOF. Maroon curve in Figure 1c shows the DRIFT spectrum of the sample after activation. All the typical features of UiO MOF family are present: i) ν(ZrOH) at 3660 cm−1, ii) ν(CH)arom between 3100-3000 cm−1, iii) ν(COO) between 1550-1300 cm−1, iv) δ(CH) between 1200-700 cm−1. The MOF is chemically stable in reaction conditions (240°C, 25% CO₂, 75% H₂); the only additional IR bands present are the one at 2350 cm−1 (CO₂) and the one at 2900 cm−1 (probabily due to a slight degradation of the MOF). The latter however, doesn’t find any degradation fragment in the acquired chromatograms.

Figure 1. (Part a) three-dimensional representation of PdCl₂-UiO-67-bpy (adapted from Ref. [2a]). (Part b) PXRD pattern and N₂ adsorption (inset) of the UiO-67-bpy MOF before (orange) and after PdCl₂ functionalization (maroon). (Part c) DRIFT spectra of H₂-activated Pd-UiO-67-bpy before starting the reaction (maroon) and during CO₂ reduction (red). Inset shows the selectivity towards the reaction products obtained, that are CO (maroon) and CH₄ (red).

4. Conclusions

Pd-UiO-67-bpy, shows a slightly lower CO2 conversion compared to the Pt system. However, the material shows a much higher selectivity towards CH4 (Figure 1c - inset), making it a good candidate to convert CO₂ into CH₄.

References

Y. Han, et al., Chem. Soc. Rev. 43 (2014) 5952; A. Corma, et al., Chem. Rev. 110 (2010) 4606.
S. Øien, et al., Chem. Mater. 27 (2015) 1042; L. Braglia, et al., Faraday Disc. 201 (2017) 265.
E.S. Gutterød, et al., Ind. Eng. Chem. Res. 56 (2017) 13206.
H. Fei and S.M. Cohen, Chem. Commun., 50 (2014) 4810; D. Gao et al., J. Am. Chem Soc., 137 (2015) 4288.

KA9

Adsorption, diffusion, and methylation of light alkenes in AFI zeotypes: insights from pulse-response TAP measurements

Evgeniy A. Redekop*, Magnus Morten, Maria Mykland, Unni Olsbye

Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo, Norway

* corresponding evgeniyr@smn.uio.no

Physico-chemical interactions of alkenes with the microporous frameworks of solid acids are crucially involved in determining outcomes of many industrially-important separation and catalytic processes such as the Methanol-to-Olefins (MTO) reaction. Herein, the transient kinetic method of Temporal Analysis of Products (TAP) is employed to investigate the behavior of C2-C4 alkenes within metal-substituted aluminophosphates in the limit of zero coverage and in a broad temperature range (323-673C). At these conditions, the rates of adsorption, intra-crystalline diffusion, and methylation reaction are controlled only by the intrinsic properties of alkenes and solid materials without the interfering influence of pore crowding. Data suggest that at the temperatures relevant for MTO reactions (>500K) alkenes have very short residence times within zeotypes, which, however, are not insignificant for >C2 alkenes and are increasing with increased acidity of the material. A simple model with reversible adsorption captures the shapes of the transient responses well in this temperature range. At lower temperatures, experimental data cannot be captured by either this simple model or by the model with spatially resolved intra-crystalline diffusion accompanied by pseudo-equilibrated adsorption at the pore mouth. We tentatively attribute the observed behavior to yet unidentified interactions of alkene double bonds with Brønsted sites of the acidic zeotypes. The implications of these novel results are discussed in relevance to precise kinetic characterization of methylation kinetics.

Figure 1. The reactor residence time of C2-C4 alkenes for SAPO-5, showing that alkenes have very low delay within the materials in the MTO-relevant temperature range >600K

References

U. Olsbye et al., Angew. Chem. Int. Ed. 51 (2012) 5810 – 583.
K. Morgan et al., Catal. Sci. Technol. 7 (2017) 2416 – 2439

KA10

iCSI – industrial Catalysis Science and Innovation – a Centre for Research-based Innovation (SFI)

Hilde J. Venvik*

Department of Chemical Engineering, NTNU – Norwegian University of Science and Engineering, 7491 Trondheim, Norway

* Hilde.j.Venvik@ntnu.no, https://www.ntnu.edu/icsi

iCSI was appointed Centre for research based innovation (SFI) by the Research Council of Norway in 2015. iCSI concerns science and innovation related to industrial processes that are key to Norwegian land-based industry, global industrial competitiveness, and future chemical processing and energy conversion with minimum environmental footprint. These processes supply key sectors of the global market (catalysts, chemicals, fertilizer, plastics, fuels, etc.); the very products that impact our food supply and standard of living the most. iCSI teams the industrial partners Yara, K.A. Rasmussen AS, Dynea, INOVYN and Haldor Topsøe AS, with the research partners University of Oslo, SINTEF and Norwegian University of Science and Technology (NTNU).

The iCSI basic vision is to establish competence and technology that promotes world-class energy and raw material efficiency for the industrial partners. iCSI will also be a strong future knowledge base for the Norwegian chemical industry, and benefit society in terms of securing jobs, reducing the energy consumption and abating harmful emissions to the environment. State-of-the-art methodology in synthesis, characterization, and kinetic investigations are applied to understand fundamental physical and chemical phenomena critical to the performance of complex catalysts operating under industrially relevant conditions. Based on this insight, predictive tools for materials, chemistry and process optimization can be developed.

The iCSI total budget is MNOK 192 (2015-2023) and NTNU is host institution. Significant researcher training in the form of ~14PhD and ~6 postdoctoral fellowships is included. iCSI has an extensive international research interface and a profile of promoting excellence and leadership of women in research and innovation.
In this contribution, the iCSI Centre Director explains the main research challenges taken on in iCSI and how the Centre is working on these. Some research highlights this far will be presented [1-4].

References

Rout, Kumar Ranjan; Fenes, Endre; Baidoo, Martina Francisca; Abdollahi, Reza; Fuglerud, Terje; Chen, De; Highly Active and Stable CeO2‐Promoted CuCl2/Al2O3 Oxychlorination Catalysts Developed by Rational Design Using a Rate Diagram of the Catalytic Cycle, ACS Catalysis, 2016, 6, 7030-7039
Pappas, Dimitrios; Borfecchia, Elisa; Dyballa, Michael Martin; Pankin, Ilia A.; Lomachenko, Kirill A.; Martini, Andrea; Signorile, Matteo; Teketel, Shewangizaw; Arstad, Bjørnar; Berlier, Gloria; Lamberti, Carlo; Bordiga, Silvia; Olsbye, Unni; Lillerud, Karl Petter; Svelle, Stian; Beato, Pablo, Methane to methanol: structure-activity relationships for Cu-CHA, Journal of the American Chemical Society, 2017, 139, 42, 14961-14975
Salman, Ata ul Rauf; Enger, Bjørm Christian; Auvray, Xavier; Lødeng, Rune; Menon, Mohan; Waller, David; Rønning, Magnus, The Catalytic oxidation of NO to NO2 for nitric acid production over a Pt/Al2O3 catalyst, Applied Catalysis A, General, 2018, 564, 142-146
Mom, Rik V.; Ivashenko, Oleksii; Frenken, Joost W.M.; Groot, Irene M.N.; Sjåstad, Anja O., The Nucleation, Alloying, and Stability of Co-Re Bimetallic Nanoparticles on Al2O3/NiAl(110), J. Phys. Chem. C, 2018, 122, 16, 8967-8975

KA11

Facile synthesis approach for core-shell TiO₂–CdS nanoparticles for enhanced photocatalytic H₂ generation from water

Muhammad Zubair¹, Ingeborg-Helene Svenum^1,2, Magnus Rønning¹, Jia Yang¹*

1 – Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), Sem Sælands vei 4, NO-7491, Trondheim, Norway
2 – SINTEF Industry, P. O. Box 4760 Torgarden, N-7465, Trondheim, Norway

* corresponding: jia.yang@ntnu.no

The exponential increase in the burning of fossil fuels to fulfill the high-energy demands is resulting in severe environmental issues and depletion of the oil reservoirs in the world. To mitigate the problems mentioned above, the use of heterogeneous photocatalysts is a promising way to generate renewable chemical energy in the form of hydrogen (H₂) from water by utilizing solar energy [1]. Among many different photocatalysts, TiO₂ is considered as ideal photocatalysts due to its stability, cost-effectiveness, and biocompatibility but having a wider band gap which can absorb only 3-5 % of the solar spectrum. Cadmium sulfide (CdS) is an ntype photocatalyst, having a band gap of 2.4 eV, which is a magnificent sensitizer to enhance the light absorption properties of the wide band gap metal oxide photocatalyst. The major drawbacks of CdS photocatalysts include a high recombination rate of excited charge carriers and the photo-corrosion associated with the holes generated in the valence band of CdS. To address these issues, heterojunction formation of CdS with other photocatalyst is considered an attractive approach [2].

The coupling of TiO₂ with CdS in the form of core-shell structure may be the key to get the higher activity and stability for photocatalytic H₂ generation due to efficient charge separation. Until present, many different TiO₂-CdS catalysts have been investigated for different photocatalytic applications including water splitting for H₂ generation [3], although there is a need to investigate the shell thickness of TiO₂ over CdS and its effect on the photocatalytic activity of the TiO₂-CdS system by using different hole scavengers.

Herein, we report the synthesis of highly efficient, cost-effective and stable photocatalyst consisting of TiO₂-CdS core-shell nanoparticles by a facile two-step hydrothermal method. The crystalline, morphological, optical and band alignment properties of the developed heterojunction photocatalyst are extensively studies by respective characterization techniques. The photocatalytic activity of the TiO₂-CdS samples is investigated for the H2 generation from water under simulated solar light at AM 1.5G conditions by using various hole scavengers. The most efficient photocatalyst, i.e., TiO₂-CdS (3:2), with the optimized TiO₂ shell thickness over CdS, exhibited the enhanced photocatalytic activity towards H₂generation from water by producing 954 μmol g-1 h-1 of hydrogen which are ~1.4 and ~1.7 times higher than pure CdS nanoparticles and pure TiO₂ respectively. The apparent quantum efficiency of 3.53% was observed by the atomized sample along with good stability by testing the photocatalysts for a longer time of consecutive 40 hours. The enhanced photocatalytic activity and stability of the core-shell TiO₂-CdS nanocomposite is attributed to the broader solar spectrum absorption, efficient photo-induced charge separation on the interface of TiO₂-CdS due to the formation of heterojunction and high surface area with a large fraction of mesopores.

Refrences

X. Chen, S. Shen, L. Guo, S.S. Mao, Chem. Rev. (2010) 6503.
M. Reza Gholipour, C.T. Dinh, F. Beland, T.O. Do, Nanoscale 7 (2015) 8187.
J. Schneider, M. Matsuoka, M. Takeuchi, J. Zhang, Y. Horiuchi, M. Anpo, D.W. Bahnemann, Chem. Rev. 114 (2014) 9919.

KA12

Photocatalytic MOFs for CO2 reduction

Eirik Mydske Thoresen, Mats Tilset, Mohamed Amedjkouh*

Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway

Photocatalysis offer environmentally friendly pathways in a variety of chemical processes, such as the production of solar fuels. One example of a solar fuel is methanol formed by photocatalytic reduction of CO2.

Metal-organic frameworks (MOFs) constitute a class of porous and crystalline hybrid materials that can be functionalized through e.g. chemical manipulation of the organic linkers.

In this work, new cyclometalated Ru(II) complexes (Figure 1) have been synthesized1 and incorporated as linkers into the MOF UiO-67 (Figure 2) by different methods. The resulting functionalized MOFs were characterized by PXRD, N₂ sorption, TGA-DSC, SEM, EDS, and UV-Vis spectroscopy. These MOFs show a significantly increased absorption of visible light compared to MOFs functionalized with chromophores like amine groups or
non-cyclometalated Ru(II) complexes.

The Ru(II)-functionalized MOFs were tested for photocatalytic CO₂ reduction using H₂ as reductant in a acetonitrile dispersion. An increasing amount of CO was detected over time of irradiation of the reaction cell. No CO was observed in darkness nor when the molecular Ru(II) complex was tested as catalyst. These results contribute to lay the foundation for the utilization of CO₂ with the help of sunlight.

Figure 1. The four Ru(II) complexes that were incorporated into the MOF UiO-67.

Figure 2. Unit cell of the MOF UiO-67.

Reference

Thoresen, E. M.; Balcells, D.; Øien-Ødegaard, S.; Hylland, K. T.; Tilset, M.; Amedjkouh, M., Cyclometalated ruthenium complexes with carboxylated ligands from a combined experimental/computational perspective. Dalton Trans. 2018, 47 (8), 2589-2601.

KA13

Effects of synthesis conditions on the properties and defectivity of metal-organic framework UiO-67

Gurpreet Kaur,¹ Sigurd Øien-Ødegaard,¹ Knut Tormodssønn Hylland¹, Andrea Lazzarini¹, Sachin Maruti Chavan¹, Silvia Bordiga^1,
2, Mats Tilset¹, Unni Olsbye¹ and Karl Petter Lillerud¹*

1 – Catalysis Section, Department of Chemistry, University of Oslo, P.O. Box 1033, N-0315 Oslo, Norway
2 – Department of Chemistry, NIS and INSTM Reference Centre, University of Torino, Via G. Quarello 15, 10135 Torino, Italy
*k.p.lillerud@kjemi.uio.no

UiO-67 is a Zr-based MOF with high thermal and chemical stability, ideally suited for incorporation of additional chemical functionality using linkers with biphenyl-type geometry. The effect of different synthesis conditions on the MOF properties is not well understood in UiO-67 as in UiO-66 [1,2]. Herein, is an improved protocol for the synthesis of UiO-67 by using a minimal amount of solvent and synthesis additives, thus diminishing the solvent usage by 82 percent. The synthesis procedure is then compared with the conventionally reported method, where we found that more amount of modulator is required as the amount of solvent is increased for the synthesis of high quality UiO-67. Moreover, the synthesized compound shows high thermal stability, and contains considerably less impurities and residues from the synthesis. This protocol is verified in batch production of up to 170 g MOF, and may thus contribute to significant waste reduction.

Figure 1. Scanning electron micrographs of UiO-67 synthesized with increasing amount of modulator a) 0 eq, b) 3 eq, c) 6 eq, d) 9 eq, e) 12 eq and f) 15 eq in presence of 50 eq of DMF.

References

Schaate, A.; Roy, P.; Godt, A.; Lippke, J.; Waltz, F.; Wiebcke, M.; Behrens, P., Modulated Synthesis of Zr‐Based Metal–Organic Frameworks: From Nano to Single Crystals. Chemistry – A European Journal 2011, 17 (24), 6643-6651.
Gutov, O. V.; Hevia, M. G.; Escudero-Adán, E. C.; Shafir, A., Metal–Organic Framework (MOF) Defects under Control: Insights into the Missing Linker Sites and Their Implication in the Reactivity of Zirconium-Based Frameworks. Inorganic Chemistry 2015, 54 (17), 8396-8400.

HI - Kjemiens historie

HI1

Heinrich Goldschmidt: Odd Hassels veileder

Robert Marc Friedman

Institutt for arkeologi, konservering og historie, Universitetet i Oslo

Heinrich Goldschmidt (1857-1937) er lite kjent i norsk vitenskapshistorie. Han flyttet til Norge i 1901 som Peter Waages etterfølger og gikk av i 1929. På grunn av mangel på kilder vet vi lite om hans liv som professor, forsker og innvandrer utover grunnleggende fakta. Han publisert over to hundre vitenskapelige artikler og var en dyktig foreleser i nesten tretti år i Norge. Goldschmidts viktigste bidrag til norsk vitenskap var sønnen Victor Moritz og studenten Odd Hassel. Detaljer dukker opp likevel i diverse arkiv som peker mot et antall spørsmål som er verdt å stille, selv om svarene må vente. Hans vitenskapelige trening og tidlig profesjonelle erfaring var upåklagelig og nyskapende i at han kombinert klassisk tysk organisk kjemi med den nye fysikalske kjemien. Før han kom til Norge arbeidet han i Praha, Zürich, Amsterdam, Heidelberg. Hvorfor valgte han å forlate Heidelberg for Kristiania? Viste han om det store opprøret i Kristiania mot å ansette en utlending? Det var bare i siste øyeblikk at et flertall i Kollegiet stemte for ansettelsen. Og selv om mange professorer ønsket ham velkommen, var stemning i laboratoriet og kjemimiljøet påvirket av den tidligere motstanden og av Goldschmidts fremmede akademisk kultur og fremmed etnisk bakgrunn. Mange brev viser at rasisme ikke var ukjent i Norge. Muligens var Goldschmidt og sønnens erfaringer som flinke fremmede ved Mat-nat fakultetet, et moment hvorfor de alltid sto klar til å stille opp for Odd Hassel, som også var betraktet som annerledes og en outsider.

HI2

Da Odd Hassel ble arrestert

Jorunn Sem Fure

Telemark Museum, Skien

Den tyske okkupasjonen fikk store følger for forholdene på universitetet. Universitets ledelse ble fra 1941 lagt direkte under NS-statsråden, og hensikten var å omforme landets høyeste læresete til en lojal institusjon som skulle tjene en nasjonalsosialistisk nyordning av alle samfunnsområder. De ulike fagene ble utfordret på ulike områder. Studenter og ansatte ved Det matematisk- naturvitenskapelige fakultetet ble stilt over vanskelige valg. Noen fortsatte studier og forskning uavhengig av de politiske forholdene i den grad det var mulig, noen valgte å aktivt støtte den nye ordningen. Blant de som valgte ulike former for aktiv motstand, finner vi Odd Hassel og flere av hans kolleger. For disse var det naturlig å sette sine spesialkunnskaper inn i kampen mot nazismen, men det skjedde ikke uten risiko og dramatiske følger. Den 15. oktober 1943 ble Odd Hassel og ni andre universitetslærer og 63 studenter arrester av det norske statspolitiet og ført til Berg, det norske statspolitiets leir. Maten var elendig og flere ble syke. Hassel ble plassert i kostebinderiet. Senere ble Hassel overført til Grini og 6.11 1944 ble han løslatt.

HI3

Otto Bastiansen: en karismatisk inspirator

Kari Kveseth

Kjemisk institutt, Universitetet i Oslo

Otto Chr. Bastiansen (1918-1995) var en grunnforskningens entreprenør. Han engasjerte seg i mye i tillegg til forskningen. Han deltok i samfunnsdebatten, i forskningspolitikken og i utvikling av universitetsdemokratiet. Han var åpen, uformell, iderik og samarbeidsorientert. Han var en stor miljøbygger og preget av en aldri sviktende optimisme.

Bastiansen var min faglige veileder, og jeg jobbet som assistent for ham i flere år. Jeg er engasjert av Kjemisk institutt i et eget prosjekt om historien til gassfase elektrondiffraksjon i Norge, et forskningsfelt startet av Odd Hassel med Bastiansen som viktig bidragsyter og viderefører. Med utgangspunkt i egen erfaring, og historieprosjektet vil jeg i foredraget belyse Bastiansens ulike engasjementer og vektlegge hans entusiasme, engasjement og evne til å inspirere.

HI4

Strukturbestemmelsen av benzen – en historie med mange feilskjær

Leiv K. Sydnes

Kjemisk institutt, Universitetet i Bergen

Faraday sin isolasjon av benzen i 1825 ble innledningen på en svært aktiv periode i kjemiens historie. Molekylformelen ble grobunn for mange fantasifull strukturforslag, og mangelen på kunnskaper om karbons bindingsforhold nørte opp under kreativiteten. Mange spenstige strukturforslag ble derfor lansert før Kekulés tanker fikk gjennomslag og ble den etablerte sannhet.

I mer enn 50 år bølget diskusjonen fram og tilbake før konklusjoner ble trukket og feil og mangler ble avdekket eller sannsynliggjort for godt. Noen vil hevde at en masse tid ble kastet bort, andre at denne perioden er et glimrende eksempel hvordan diskusjon skal føres mellom forskere. Uansett har det vist seg at flere av de spektakulære forslagene som ble lansert, senere har latt seg realisere ved å utføre kjemiske reaksjoner på kontrollert vis.

Men historien slutter ikke med det. Etter at Kekulé ble berømt på grunn av sitt bidrag til struktur-bestemmelsen av benzen dukket det opp beskyldninger om det vi i dag kaller dårlig forskningsetikk. Strukturoppklaringen av benzen er derfor beheftet med feil av ymse slag, noe som vil bli presentert i foredraget.

HI5

Hør Odd Hassel bli intervjuet med mine kommentarer

Bjørn Pedersen

Kjemisk institutt, Universitetet i Oslo

Per Andersen (1919-2004) og Christian Rømming (1928-2017) intervjuet professor Odd Hassel (1897-1981) ca. ett år før han døde. Både Per og Christian hadde hatt Hassel som veileder i hovedfagsstudiet, og begge hadde vært knyttet til avdeling for fysikalsk kjemi fra de var hovedfagsstudenter så de kjente ham godt.

Intervjuet er bevart på en CD som oppbevares på Kjemisk institutt. Hassel var ikke enkel å intervjue, og intervjuerne spurte ham ikke om mye som vi undres over i dag. De spurte ham bl. a. ikke om hans tid i Berlin 1923-25 da han lærte å bestemme krystallstrukturer med røntgendiffraksjon. Hans veileder var Herman Mark (1895-1992) som senere ble en berømt polymerkjemiker. I foredraget vil jeg spille av utvalgte deler av CD-en og gi mine kommentarer.

KI - Kjemometri

KI1

Bruk av kjemometri i medisinske problemstillinger - trenger vi det?

Tone F. Bathen

MR avbildning og MR spektroskopi er metoder som baseres på de samme grunnleggende fysiske prinsipper, hvor magnetfelt og radiobølger gjør det mulig å fremstille bilder og spekter. MR avbildning har vært igjennom en rivende utvikling de siste 30 årene, og er nå en sentral metode ved diagnostikk og behandling av de fleste typer kreft. Samtidig har bruksområdet for MR spektroskopi beveget seg fra å være et verktøy for strukturoppklaring i syntetisk kjemi til også å bli et nyttig medisinsk forskningsverktøy for deteksjon av metabolske biomarkører (Metabolomikk). Mens kjemometri har vært et sentralt verktøy helt fra metabolomikkens spede begynnelse, er radiologifaget fortsatt preget av manuell og kvalitativ lesning.

I denne forelesningen vil jeg benytte eksempler fra MR forskning som belyser nødvendigheten av kjemometri for å få full uttelling av informasjonsrike data.

KI2

Bruk av kjemometri til persontilpasset forebygging av livsstilssykdommer gjennom livsløpet.

Olav M. Kvalheim

Kjemisk institutt, Universitetet i Bergen

Sykdommer knyttet til livsstil øker som et resultat av en samfunnsutvikling med blant annet mindre fysisk aktivitet og mindre variert kosthold med større innslag av hurtigmat og industrielt fremstilt ferdigmat. Dette påvirker fettstoffskiftet i en ugunstig retning som kan føre til utvikling av type 2 diabetes og hjerte/kar-sykdommer. Fettstoffskiftet innebærer transporter av lipider og kan måles på molekylært nivå i serum med bruk av kjemiske analysemetoder. Lipidtransporten utføres av lipoproteiner som kan måles med HPLC og proton NMR. Ved å lage kalibreringsmodeller mellom HPLC og NMR, kan man bruke NMR og multivariat modellering har vi utviklet en hurtigmetode for å kvantifisere opp mot 100 klasser av lipoproteiner, mens det vanlige lipidpanelet kun gir LDL, HDL og total kolesterol samt total triglyserid. Mønsteret av lipoproteiner påvirkes av kjønn og alder i tillegg til livsstilsfaktorer. Forskere ved UiB, NIH, HVL, Helse Førde og NTNU har deltatt i prosjekter der tusenvis av serumprøver er analysert og det er laget modeller som viser hvordan lipoproteinmønsteret påvirkes av forskjellige faktorer som kjønn, alder, fysisk aktivitet, BMI og nivå av fettsyrer. Dette åpner muligheten til å fokusere på forebygging av livsstilssykdom med tidlig identifikasjon av individer i risikosonen med bruk av lipoproteinanalyser og påfølgende intervensjon og kontroll av resultat.

Foredraget vil vise noen eksempler på bruk av kjemometri i denne konteksten.

KI3

Gi prosess-operatørene eierskapet til Big Data.

Harald Martens

Idletechs AS / Inst. teknisk kybernetikk NTNU

Selektivitet: ja, men ikke i rådataene. Måletekniske rådata kan godt ha store, systematiske interferens-effekter. Selektivitet sikres i stedet ved hjelp av multivariat kalibrering basert på f.eks. mange-kanals hurtigmålinger (spektroskopi osv). Aller best blir slik kalibrering dersom man kombinerer fysikk-basert modellering og data-drevet modellering. Dette ble f.eks. brukt da NASA fant vann på Mars, ved hjelp av spektroskopisk EMSC modellering og PLS regresjon, implementert i det norske gjør-det-selv kjemometriprogrammet The Unscrambler.

Industrielle stordata: I prosessindustrien er digitalisering et brennhett tema. Ved å sikre en disiplinert strøm av relevante måledata, blir det i prinsippet mulig å få bedre oversikt over prosessen, og få bedre alarmhåndtering. Men det vil bare funke dersom man har gode verktøy til å tolke dataene, og til å få ned antall falske alarmer.

Ved Inst. teknisk kybernetikk bygger man nå opp et nytt, industriorientert fagmiljø for å kombinere kjemometriens multivariate myke modellering med prosess-styringens avanserte dynamikk-modellering.

I firmaet Idletechs AS – et spin-off fra ITK/NTNU – har vi kombinert og videreutviklet kjemometri-, kybernetikk- og maskinlærings- metoder, til å håndtere «evig-varende», høydimensjonale strømmer av industrielle eller biomedisinske stordata: «Explainable AI». Typiske anvendelser: Termisk video og mekanisk vibrasjonsmåling til overvåking av maskineri, hyperspektral video av kjemiske prosesser, tørkeprosesser osv.

Mennesket og maskinene: Metodene våre kan brukes autonomt, uten menneskelig innsats, i f.eks. satellitter og romfartøyer. Men hovedfokuset er likevel på å gjøre gode fagarbeidere enda bedre, ved at de får bedre verktøy til å overblikke og drifte komplekse produksjonsprosesser. Om kunstig intelligens skaper en fremtidig kamp mellom menneske og datamaskinene, er vi på parti med menneskene.

KI4

Kjemometri og magi i matindustrien.

Ingrid Måge

Nifima

Spektroskopi kan brukes til å måle en lang rekke kvalitetsegenskaper i mat, både direkte på produksjonslinja og i laboratoriet. Nærinfrarød (NIR) er den mest brukte teknikken, men mer høyoppløselige teknikker som for eksempel Raman og FT-IR har hatt en rivende utvikling de siste årene. Interessen fra matindustrien er økende fordi denne type teknologi og metodikk er avgjørende for å løse noen av dens fremste utfordringer: Å oppnå stabil og riktig produktkvalitet, optimal utnyttelse av råvarer, minimering av svinn og dermed en lønnsom og bærekraftig matproduksjon.

Jeg vil vise et knippe eksempler fra forskningsfronten på spektroskopi og kjemometri i matindustrien. Flere av løsningene vi har vært med på å utvikle er implementert og kommersialisert i tett samarbeid med både matindustrien og utstyrsleverandører. Anvendelsene er så mange og varierte at det for noen kan framstå som ren magi.

Utvalgte referanser

Wubshet, S.G., Wold, J.P., Böcker, U., Sanden, K.W., Afseth, N.K., 2019. Raman spectroscopy for quantification of residual calcium and total ash in mechanically deboned chicken meat. Food Control 95, 267–273.
Wubshet, S.G., Wold, J.P., Afseth, N.K., Böcker, U., Lindberg, D., Ihunegbo, F.N., Måge, I., 2018. Feed-Forward Prediction of Product Qualities in Enzymatic Protein Hydrolysis of Poultry By-products: a Spectroscopic Approach. Food Bioprocess Technol.
Wold, J.P., Måge, I., Løvland, A., Sanden, K.W., Ofstad, R., 2018. Near-infrared spectroscopy detects woody breast syndrome in chicken fillets by the markers protein content and degree of water binding. Poult. Sci.
Måge, I., Wold, J.P., Bjerke, F., Segtnan, V., 2013. On-line sorting of meat trimmings into targeted fat categories. J. Food Eng. 115, 306–313.
Wold, J.P., Kermit, M., Woll, A., 2010. Rapid nondestructive determination of edible meat content in crabs (Cancer Pagurus) by Near-Infrared Imaging spectroscopy. Appl. Spectrosc. 64, 691–699.

UN - Kjemiundervisning

UN1

Vitenskap på kjøkkenet - Om kaker som (ikke) faller sammen og egg som kokes fra innsida og ut

Erik Fooladi

Høgskolen i Volda

Må biffen romtemperes før den stekes? Faller kaka sammen hvis du ikke er forsiktig når du tar den ut av ovnen? Og er det mulig å lage eplepai helt uten epler? Når du koker et egg eller setter en gjærdeig jobber du med kjemiske, biologiske og fysiske prosesser på kjøkkenet ditt. Samtidig bruker du håndverkskunnskap du har lært av andre eller ved å prøve deg fram selv. Men mat er også historie, kultur, identitet og sanseerfaringer. Sammen med professor i matvitenskap Anu Hopia (Universitetet i Turku) har førsteamanuensis Erik Fooladi (Høgskulen i Volda) skrevet den populærvitenskapelige boka «Kjemi på kjøkkenet: Om hvorfor kaka faller sammen og andre kjøkkenhistorier». I boka ønsker forfatterne å balansere kjemi, håndverk og smaksopplevelser, noe som kan gjøre matlagingen mer spennende, hodet litt klokere, og maten litt bedre. Og kanskje kan det til og med fremme kritisk tenkning? I foredraget vil Fooladi presentere boka og tenkningen bak den, og tilhørerne får være med på et sanselig eksperiment.

Bilde av boka

UN2

Kjemiolympiaden

Hans-Petter Hersleth og Bjørn Dalhus

Universitetet i Oslo

Kjemiolympiaden har vært arrangert helt siden 1968 og Norge har vært med siden 1982. I år er det ca 75 nasjoner som skal delta. 4 elever fra hvert land konkurrerer i både praktisk laboratoriearbeid og teori. Det er "Kjemi-OL komiteen" under NKS som står for utvelgelse og opplæring av det norske laget. Dette gjør vi i tett samarbeid med Kjemisk Institutt og det matematisk-naturvitenskapelige fakultet ved UiO. Vi står også for arrangering av den norske kjemi-OL finalen som en del av uttakingsarbeidet. I dette foredraget vil vi fortelle litt om hvordan komiteen arbeider, hvilket opplegg vi har for de norske uttakskonkurransene, litt om det internasjonale nivået og også fortelle litt fra den internasjonale finalen.

UN3

Elevforsøk til bruk i kjemi programfag

Karoline Fægri og Svein Tveit

Universitetet i Oslo

Mange av kompetansemålene i kjemi 1 og kjemi 2 krever at elevene gjennomfører elevforsøk. I denne sesjonen får deltagerne prøve ut et utvalg elevforsøk som er knyttet til kompetansemål i læreplanen for kjemi 1 eller kjemi 2. Til hvert forsøk legger vi opp til en fagdidaktisk diskusjon.

UN4

Triks i Ludo for den digitale kjemilæreren

Asbjørn Aarflot

Stavanger katedralskole

Sesjonen vil fokusere på bruk av digitale hjelpemidler i undervisningen og særlig videregående skole. Dette gjelder bruk av Marvin sketch til å tegne kjemiske strukturer og 1-HNMR spekter, autokjeminotasjon i Word med Chemistry formatter og spesialtegn i Word. En egen del vil være om bruk av Excel til å laste inn rådata og presentasjon av MS-spekter. Det blir lagt opp til egen utprøving med veiledning så ta med egen pc eller mac.

KM - Kvantekjemi og modellering

KM1

Applying coupled cluster theories to solids and surfaces in the thermodynamic limit

Andreas Grüneis

Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria

Modern electronic structure theories can predict and simulate a wealth of phenomena in surface science and solid-state physics. In order to allow for a direct comparison with experiment, such ab initio predictions have to be made in the thermodynamic limit, substantially increasing the computational cost of many-electron wave-function theories. We present a method that achieves thermodynamic limit results for periodic solids and surfaces using the coupled cluster ansatz of quantum chemistry [1]. Computational results for pressure-temperature phase diagrams of carbon allotropes as well as adsorption energies of water on hexagonal BN will be presented, demonstrating the increased efficiency of our coupled cluster theory implementation for solids and surfaces.

Reference

T. Gruber, K. Liao, T. Tsatsoulis, F. Hummel and A. GrÃ¼neis , Phys. Rev. X 8, 021043 (2018)

KM2

The Study of Coupled-Cluster Methods Using Strong Monotonicity

Andre Laestadius, Fabian Faulstich, Simen Kvaal

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo

By means of an exponential ansatz, the coupled-cluster (CC) method is a highly successful approach to treat electron correlation. The CC method and its variations have been analyzed [1,2,3,4] within the ERC project BIVAQUM [5]. This project studies a generalized variational principle - the so-called bivariational principle - where the bra and ket of the Rayleigh-Ritz quotient are treated as truly independent variables. This brief presentation aims at explaining the basic mathematical concepts used to prove a locally unique solution of the CC methods. This includes notions such as strong monotonicity and Lipschitz continuity. Their connections to a HOMO-LUMO gap and the fluctuation potential defined as the difference between the system's Hamiltonian and the Fock operator are here further elaborated.

References

A. Laestadius and S. Kvaal. Analysis of the Extended Coupled-Cluster Method in Quantum Chemistry, SIAM J. Numer. Anal. 56, 660, 2018.
F. Faulstich et al. Analysis of the Coupled-Cluster Method Tailored by Tensor-Network States in Quantum Chemistry, arXiv:1802.05699, 2018.
A. Laestadius and F. Faulstich. The Coupled-Cluster Formalism - A Mathematical Perspective, arXiv:1804.08134, 2018.
F. Faulstich et al. Numerical and Theoretical Aspects of the DMRG-TCC Method Exemplified by the Nitrogen Dimer, to appear on arXiv 2018.
S. Kvaal, http://www.bivaqum.no

KM3

An efficient pseudo-spectral method for the description of atomic electronic wave functions - application to the hydrogen atom in a uniform magnetic field

Clemens Woywod¹, Susmita Roy², Kiran Maiti³ and Kenneth Ruud⁴

Department Chemie, Technische Universitaet Muenchen

Research Unit of Buhl-Strohmaier Foundation for Cerebral Palsy and Paediatric Neuroorthopaedics, Orthopaedic Department, Klinikum rechts der Isar, Technische Universitaet Muenchen

Max Planck Institut fuer Quantenoptik, Garching

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, The University of Tromso - The Arctic University of Norway

The mapping of an electronic state on a real-space support lattice may offer advantages over a basis set ansatz in cases where there are linear dependences due to basis set overcompleteness or when strong internal or external fields are present. Such discretization methods are also of interest because they allow for the convenient numerical integration of matrix elements of local operators. We have developed a pseudo-spectral approach to the numerical solution of the time-dependent and time-independent Schroedinger equations describing electronic motion in atoms and atomic ions in terms of a spherical coordinate system. A key feature of this scheme is the construction of a Variational Basis Representation (VBR) for the non-local component and of a Generalized Finite Basis Representation (GFBR) for the local component of the electronic Hamiltonian operator. Radial Hamiltonian eigenfunctions χ_nl;β(r) of the H atom-like system and spherical harmonics form the basis set. Two special cases of this approach are explored: In one case, the functions of the field-free H atom are used as the elements of the basis set, and in the second case, each radial basis function has been obtained by variationally optimizing a shielding parameter beta to yield a minimum energy for a particular eigenstate of the H atom in a uniform magnetic field. We derive a new quadrature rule of nearly Gaussian accuracy for the computation of matrix elements of local operators between radial basis functions and perform numerical evaluation of local operator matrix elements involving spherical harmonics. With this combination of radial and angular quadrature prescriptions we ensure to a good approximation the discrete orthogonality of Hamiltonian eigenfunctions of H atom-like systems for summation over the grid points. The pseudo-spectral approach presented here is applied to two model systems: the field-free H atom and the H atom in a uniform magnetic field. The results demonstrate the potential of this method for the description of challenging systems such as highly charged atomic ions.

Reference

Woywod, Roy, Maiti and Ruud, Chemical Physics, submitted

KM4

Modelling nanoscale friction of adsorbed molecules

Astrid de Wijn

Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway

Friction between solid surfaces is an important phenomenon in everyday life. A large portion of the total energy production in industrialised countries is lost through friction and wear. Friction is a very complex phenomenon with dynamics happening on many length and time scales. At the most basic level, however, is the dissipation at the nano-scale level. At this level, real sliding interfaces can still be fairly complex. Often, there are molecules adsorbed on the surfaces, originating from the atmosphere or additives that have been put in a lubricant to protect the surface from wear, corrosion, etc.

I will discuss theoretical approaches to studying how adsorbed molecules affect the friction at the nano scale, using simple models and molecular-dynamics simulations.

KM5

Molecular dynamics in a density dependent inhomogeneous dielectric

Sigbjørn Løland Bore, Hima Bindu Kolli, Toshihiro Kawakatsu, Giuseppe Milano, and Michele Cascella

University of Oslo

A new molecular dynamics method for computing electrostatic forces in a inhomogeneous density dependent dielectric is presented. Using a hybrid particle field approach[1], forces acting on charged particles and the particles making up the dielectric are derived. These forces are computed from the electrostatic potential, obtained by solving the generalized Poisson's equation. Benchmarking of the method, shows that it is able to describe partitioning phenomena due to differences in dielectric properties in a binary phase system. Furthermore, for a charged lipid bilayer, it shown that forces on the particles making up the dielectric have a significant contribution to the force density around the membrane, with net effect of contracting the width of the membrane.

References

Hybrid particle-field molecular dynamics simulations for dense polymer systems
Giuseppe Milano1, and Toshihiro Kawakatsu The Journal of Chemical Physics, (2009) 130:21

KM6

Self-Assembly of α-Tocopherol Transfer Protein Nanoparticles: A Patchy Protein Model

Raphael Peltzer,† Hima Bindu Kolli,† Achim Stocker,‡ and Michele Cascella,†

†Department of Chemistry, and Hylleraas Centre for Quantum Molecular Sciences, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
‡Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland

I describe the mechanism of self-aggregation of α –tocopherol transfer protein into a spherical
nanocage employing Monte Carlo simulations. The protein is modeled by a patchy coarse-grained representation, where the protein−protein interfaces, determined in the past by X-ray diff raction, are represented by simplified two-body interaction potentials. Our results show that the oligomerization kinetics proceeds in two steps, with the formation of metastable trimeric units and the subsequent assembly into the spherical aggregates. Data are in agreement with experimental observations regarding the prevalence of different aggregation states at specific ambient conditions. Finally, our results indicate a route for the experimental stabilization of the trimer, crucial for the understanding of the physiological role of such aggregates in vitamin E body trafficking.

KM7

DrawMol a new program to visualize molecular properties - Application to Magnetically Induced Current of Helicene molecules

Vincent LIEGEOIS

Laboratory of Theoretical Chemistry, Namur Institute of Structured Matter (NISM), University of Namur, rue de Bruxelles 61, 5000 Namur, Belgium.

DrawMol is a full-featured program to build molecular structures from scratch (and to generate the input files for Gamess-US and Gaussian quantum chemistry packages) as well as to visualize molecular properties. In addition to the visualization of the structures, the molecular orbitals and the dipole moments that are commonly found in other programs, DrawMol also represents the polarizability and hyper-polarizability using the unit sphere representation, the polarizability ellipsoid, the vibrational normal modes together with the IR vectors, the NMR chemical shifts, and the magnetically induced current density. This program is for Mac only and is available on sale on the Mac App Store since November 2016.
In this contribution, I will present some magnetically induced current density calculations performed on helicene molecules. For that, Gaussian 16 program together with the GIMIC code [1] have been used. Starting from [6]Helicene molecule, we have investigated larger and larger helicenes up to 20 fused benzene rings. Among the interesting features, we have noticed that the two extrema rings bear the largest induced current values as well as the smallest NICS(0) values. From [7]Helicene, we have substituted 1, 3 and 4 benzene rings by either pyrrole or thiophene moieties. Results have shown that the 5-membered rings were having the smallest current value.

Fig. 1. Streamline representation of the magnetically induced current of [7]helicene. The external magnetic field is pointing toward the reader.

Reference

M. Rauhalahti, S. Taubert, D. Sundholm, V. Liégeois, Phys. Chem. Chem. Phys. 19 (2017) 7124.

KM8

Relativistic real-time and linear response TDDFT approaches to electron absorption and circular dichroism spectroscopies

Lukas Konecny¹, Marius Kadek¹, Stanislav Komorovsky², Kenneth Ruud¹, Michal Repisky¹

¹Hylleraas Centre for Quantum Molecular Sciences, UiT—The Arctic university of Norway, Tromsø, Norway
²Institute of Inorganic Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia

We present implementation and applications of two methods for the evaluation of electron absorption (EAS) and circular dichroism (ECD) spectra available in the relativistic quantum chemistry density functional theory (DFT) program ReSpect (www.respectprogram.org). First is the electron dynamics (real-time time-dependent DFT) based on a direct propagation of electron density matrix in time. The spectra are obtained by the Fourier transformation of time-dependent induced electric or magnetic dipole moments recorded during the propagation. Such a method allows to access spectra in various regions, including near-resonant frequencies, from a single simulation, as well as to treat molecules subjected to strong or arbitrarily time-dependent external fields without the need to calculate the response kernels. [1]

A cost-efficient alternative in the weak field regime is the damped linear response theory that is based on perturbation expansion. An algebraic response equation is solved using the iterative subspace algorithm in the frequency domain to directly yield the spectral function for the frequencies of interest. [2]

Both scalar relativistic effects and spin-orbit coupling are treated variationally by means of the 4-component Dirac–Coulomb Hamiltonian represented in the basis of restricted kinetically balanced Gaussian functions exploiting the noncollinear Kramers unrestricted formalism, as well as by the computationally efficient quasi-relativistic 2-component X2C Hamiltonian obtained from the original 4-component Hamiltonian by adiabatic decoupling transformation formulated entirely in matrix algebra.[3].

We demonstrate the performance of the developed methods by calculating EAS and ECD spectra of a number of benchmark systems including heavy-element containing molecules in valence as well as X-ray regions.

References

M. Repisky, L. Konecny, M. Kadek, S. Komorovsky, O. L. Malkin, V. G Malkin, K. Ruud, J. Chem. Theory Comput., 11, 980 (2015).
L. Konecny, M. Repisky, K. Ruud, S. Komorovsky, in preparation
L. Konecny, M. Kadek, S. Komorovsky, O. L. Malkin, K. Ruud, M. Repisky, J. Chem. Theory Comput., 12, 5823 (2016).

KM9

Time-Dependent Coupled-Cluster Theory

Thomas Bondo Pedersen and Simen Kvaal

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo

Coupled-cluster theory is the most successful wave function-based method in quantum chemistry today. It provides highly accurate energies and properties of electronic ground states, excitation energies and excitation strengths, and excited-state properties, as long as the ground state is dominated by a single electron configuration. Spectroscopic properties are computed using perturbation theory with the underlying assumption that the external field is sufficiently weak. Motivated by the investments over the last decade in the development of extremely brilliant and coherent laser sources, we present a nonperturbative approach to spectroscopic processes based on direct propagation of the coupled-cluster state in the presence of an intense and short laser pulse. The main focus of the talk will be on the time-propagation itself, interpretation of the time signals, and on the suitability of coupled-cluster theory for the description of molecular electronic systems in the extreme environment of a laser pulse.

KM10

Selective CO₂conversion with Rh/bisphosphine-thiourea (ZhaoPhos) catalyst

Ljiljana Pavlović, Janakiram Vaitla, Annette Bayer, Kathrin H. Hopmann

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway ljiljana.pavlovic@uit.no

Transition metal-catalzyed enantioselective hydrocarboxyalation of α,β-unsaturated esters could provide a method to synthesise chiral carboxylic acids, which are the main components of many drugs. Thus, the design of enantioselective and sustainable catalysts for this reaction with CO_2, presents a big challenge in the pharmaceutical industry. Only one asymmetric CO₂-based hydrocarboxylation reaction has been reported, involving a rhodium complex with a bidentate SegPhos ligand, which in the presence of ZnEt₂ carboxylates α,β-unsaturated esters with up to 66% enantiomeric excess. [1] Our previous theoretical study revealed that during during the C -CO₂ bond formation, the CO₂molecule interacts with neither the rhodium complex nor the organozinc additive. [2] This appears to be in contrast to other CO₂ insertion reactions, where CO₂−metal interactions have been predicted. Additinally, the substrates show an unusual coordination mode during CO₂
insertion, with the nucleophilic carbon positioned up to 3.6 Å away from rhodium.

Based on these findings, we further investigated the potential for enantioselective CO2 conversion. The asymmetric CO2-based hydrocarboxylation reaction has been studied using density functional theory (PBE-D2/IEFPCM). For this purpose, chiral transition metal based catalysts can be employed, which through selective interactions with the substrate, are able to favour the formation of only one enantiomer. Many ligands were studied: PHOX, SegPhos and ZhaoPhos, but all of them gave little selectivity. On the contrary, the use of a novel and modified ZhaoPhos ligand, that has not been previously used in hydrocarboxylation, gave a good selectivity in computations. It has been known that thiourea, which is linked to the ligand, works as a hydrogen donor, thus it activates the substrate and provides high conversion and excellent enantioselectivity in many Rh-based hydrogenation reactions.[3]Futhrer investigation of this efficent catalyst are ongoing in our labaratory.

References

Kawashima, S.; Aikawa, K.; Mikami, K.; Eur. J. Org. Chem. 2016, 3166-3170.
Pavlovic, Lj.; Vaitla, J., Bayer, A.;Hopmann, K.H.; Organometallics 2018 37, 941−948
Q. Zhao, S. Li, K. Huang, R. Wang and X. Zhang; Org. Lett., 2013,15, 4014–4017

KM11

Decarbonylative dehydration of fatty acids: New mechanistic insight

Sondre H.H. Eliasson, Anamitra Chatterjee, Vidar R. Jensen

Kjemisk Institutt, Universitetet i Bergen

Linear α-olefins(LAOs) are key commodity chemicals and petrochemical intermediates currently produced from fossil resources. However, renewable resources may also provide α-olefins. As we have recently reviewed,[1] one attractive biomass for such production is fatty acids and their derivatives. From fatty acids, α-olefins may be reached via transition-metal-catalyzed deoxygenation, the perhaps most promising variation of which is decarbonylative dehydration.[1] However, the best decarbonylative dehydration catalysts obtained to date are not active and stable enough for industrial use. Fortunately, designing more active and stable catalysts is now being facilitated by the arrival of the first mechanistic insight from density functional theory (DFT) studies[2-5] and the first well-defined precatalyst for this reaction, Pd(cinnamyl)Cl(DPEPhos),[6] which offers superior activity at relatively low temperatures (110 °C). Recent DFT calculations show how the DPEPhos ligand contributes to a low overall barrier and high α-selectivity by switching from bidentate to monodentate binding mode prior to the rate-determining β-H-elimination step.[7] Retaining one of the Pdâ€“P bonds of the DPEPhos ligand while dissociating acetate and CO is advantageous in dipolar solvents such as DMPU or the green alternative γ-valerolactone (GVL),[8] and eliminates the large excess of phosphine otherwise needed for catalyst regeneration and sustained activity.[1] The effect of the DPEPhos binding mode switching suggests that new and improved ligands might be designed that combine strongly coordinating with more labile binding sites.

Figure 1.

References

A. Chatterjee, S. H. Hopen Eliasson and V. R. Jensen, Catalysis Science & Technology, 2018, 8, 1487-1499.
M. A. OrtuÃ±o, B. Dereli and C. J. Cramer, Inorg. Chem., 2016, 55, 4124-4131
A. John, M. O. Miranda, K. Ding, B. Dereli, M. A. OrtuÃ±o, A. M. LaPointe, G. W. Coates, C. J. Cramer and W. B. Tolman, Organometallics, 2016, 35, 2391-2400
A. John, B. Dereli, M. A. OrtuÃ±o, H. E. Johnson, M. A. Hillmyer, C. J. Cramer and W. B. Tolman, Organometallics, 2017, 36, 2956-2964.
S. H. H. Eliasson, A. Chatterjee, G. Occhipinti and V. R. Jensen, Inorganics, 2017, 5, 87.
A. Chatterjee, S. H. H. Eliasson, K. W. TÃ¶rnroos and V. R. Jensen, ACS Catal., 2016, 6, 7784-7789.
S. H. H. Eliasson, A. Chatterjee and V. R. Jensen, The mechanism for selective and active decarbonylative dehydration of fatty acids, manuscript in progress
A. Chatterjee, S. H. H. Eliasson and V. R. Jensen, Green solvent for the synthesis of linear a-olefins from fatty acids, unpublished work.

KM12

Catalytic Hydrogenation of Amides to Methanol and Amines from a Computational Perspective.

Lluis Artus Suarez, David Balcells, Mats Tilset, Ainara Nova

University of Oslo

CO2 is abundant, cheap, non-flammable and has low toxicity, making it an ideal renewable carbon feedstock. Recently, the conversion of CO2 to methanol was performed in a one-pot reaction with a ruthenium bifunctional catalyst, in the presence of amines.[1] The participation of amides as intermediates in the mechanism of this reaction prompted us to study their reduction to methanol, with the aim of developing a rational approach to the design of more active and robust catalytic systems. In this work, the mechanism for the hydrogenation of formanilide and dimethyl formamide (DMF) to methanol with an iron catalyst (Figure) has been studied with a DFT method and compared to the experimental results of Bernskoetter and Hazari.[2] The microkinetic models derived from the DFT calculations reproduced the high conversions obtained with formanilide and the need of using the latter as co-catalyst in the hydrogenation of DMF. The computational studies revealed a complex reaction network arising from three consecutive processes; namely 1) the hydrogenation of the amide C=O bond, 2) the protonolysis of the C–N bond of an hemiaminal intermediate and 3) the hydrogenation of formaldehyde. Interestingly, the mechanism of process 2) depends on the nature of the substrate.

Figure. Reaction mechanism postulated for the iron-catalyzed hydrogenation of amides.

References

M. S. Sandford et. al., J. Am. Chem. Soc. 2015, 137, 1028-1031.
N. Hazari, W. H. Bernskoetter et. al., Organometallics, 2017, 36, 409-416.

KM13

DigiBiotics: discovering novel antimicrobial molecules from Arctic marine fungi

Karolina Solheimslid Eikås, Kenneth Ruud, Maarten Beerepoot and Bjørn Olav Bransdal

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway

The DigiBiotics project aims to discover novel antimicrobial molecules from Arctic marine fungi. My part of the project is to develop a novel computational protocol for structure determination of the complex and chiral cyclic polypeptides found in the fungi. The molecules of main interest in this project are larger than the clinical antibiotics used today and there is a need for an efficient and reliable protocol for structural determination of these molecules. Due to the large and complex molecule structure, this protocol will combine experimental and computational spectroscopy to reach the gold standard for the determination of absolute configuration. Several different spectroscopies will be used, but my project will focus on the vibrational chiroptical methods Raman Optical Activity (ROA) and Vibrational Circular Dichroism (VCD). In my presentation I will point out why we need these types of spectroscopy and the strategy to develop this protocol.

Figure 1. From Marine Fungi to commercial antibiotics. The picture to the left is taken by Marte Jensen (UiT Norges arktiske universitett), the figure in the middle is taken from ref [1] and to the right an illustration: www.colourbox.com

Reference

Kathrin H. Hopmann; Kenneth Ruud; Magdalena Pecul; Andrzej Kudelski; Martin DraÄÃnskÃ½; Petr BouÅ™; J. Phys. Chem. B 2011, 115, 4128-4137. DOI: 10.1021/jp110662w

KM14

Peptide fibrillization revealed by two-photon absorption

Maarten Beerepoot¹, Md. Mehboob Alam¹, Kenneth Ruud¹, Robert Zalesny² and Piotr Hanczyc³

¹Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, maarten.beerepoot@uit.no
²Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wroclaw University of Science and Technology, Poland
³Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland

Peptide fibrillization and the resulting amyloid fibres are responsibles for various diseases among which Parkonson's and Alzheimer's. Experimental work has shown strong non-linear absorption as a result of peptide fibrillization, which has been explained by though-space intermolecular interactions between aromatic residues in different peptides in the same fibril [1]. In another study, quantum chemical calculation have shown that a similar mechanism of through-space charge transfer is responsible for enhanced two-photon absorption in the globular yellow fluorescent protein [2].

The aim of the present project is to use experimental multiphoton absorption techniques in combination with quantum chemical calculations to investigate whether intermolecular charge transfer can indeed explain the enhanced multiphoton absorption in protein fibrils. The combination of experimental evidence with mechanistic insights from quantum chemical calculations may help in the development of new techniques to detect amyloid fibrils and/or in the development of new materials for applications in nanotechnology.

References

Hanczyc, Samoc and Norden, "Multiphoton absorption in amyloid protein fibres", Nature Photonics 7 (2013), p. 969.
Beerepoot, Friese and Ruud, "Intermolecular charge transfer enhances two- photon absorption in yellow fluorescent protein", Phys. Chem. Chem. Phys. 16 (2014), p. 5958

KM15

Molecular vibrations with polarizable embedding

Karen Oda Hjorth Dundas, Kenneth Ruud, Maarten Beerepoot, Magnus Ringholm, Magnus Olsen

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway

Methods combining quantum mechanical (QM) methods and molecular mechanics (MM) methods are important tools when it comes to studying larger molecular systems. One example of such a QM/MM method is Polarizable Embedding (PE) where a central core is modelled with a QM method of choice (DFT) and the surrounding environment is classically modelled by placing multipoles an polarizabilities on each atomic site. In this way you can in addition to looking at the QM region calculated it's electrostatic and induced interaction with the environment. We are now working on combining this with a recursive response theory library so that we can look at various molecular properties, and specifically molecular vibrations, for large molecular systems. This will allow us to look at for instance IR or Raman properties for solutions or biomolecules in an efficient fashion.

KM16

RNA structure and dynamics combining molecular simulations and experiments.

Giovanni Bussi

SISSA, Trieste, Italia

RNA structure and dynamics combining molecular simulations and experiments . Ribonucleic acid (RNA) has a fundamental role in cell biology. However, experimental characterization of RNAs dynamical behavior at atomistic level is difficult. Molecular simulations (MD) at atomistic detail in combination with state-of-the-art free-energy techniques could in principle bridge the gap providing an unparalleled perspective on the mechanism and dynamics of RNA folding and conformational transitions. However, current empirical force fields used to model RNA are not yet accurate enough to predict structural dynamics in agreement with solution phase experiments. In this talk I will show how it is possible to combine solution experiments and MD simulations to reliably predict RNA structural dynamics using both the maximum entropy and the maximum parsimony principles [1,2] in order to recover excited states that are difficult to directly visualize in experiment. In addition, I will show how experimental data can be used in order to systematically improve the accuracy of existing force fields [3]. [1] Cesari, Reisser, Bussi, Computation (2018). [2] Reisser et al, in preparation (2018). [3] Cesari et al, in preparation (2018).

KM17

Role of time-reversal symmetry in relativistic band-structure calculations of solids

Marius Kadek, Michal Repisky, Kenneth Ruud

Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT – The Arctic University of Norway, Tromsø, Norway

In the talk, I will outline the concept of the time-reversal symmetry in the context of relativistic electronic structure theory of periodic systems. I will explore the consequences of the time-reversal symmetry and the spin–orbit coupling on the structure of operators and matrices expressed using the restricted kinetically balanced Gaussian-type orbitals [1], and extend the quaternion formalism [2,3] to reciprocal space [4]. Some properties of spin–orbit-coupled two-dimensional materials will be discussed, as well as possible future directions and applications of our relativistic Gaussian-based all-electron method that employs the 4-component Dirac–Coulomb Hamiltonian.

Fig. 1. Dirac cones appearing in the band structure surface plot of the highest occupied band (blue) and the lowest unoccupied band (orange) of the two-dimensional germanene.

References

R. E. Stanton and S. Havriliak, J. Chem. Phys. 81, 1910 (1984).
T. Saue, K. FÃ¦gri, T. Helgaker, and O. Gropen, Mol. Phys. 91, 937 (1997).
L. Konecny, M. Kadek, S. Komorovsky, K. Ruud, and M. Repisky, J. Chem. Phys. (2018), (to be published).
M. Kadek, M. Repisky, and K. Ruud. in preparation.

KM18

Contribution of the aromatic amino acids in membrane binding of peripheral proteins using Free Energy Perturbation.

Qaiser Waheed, Hanif M. Khan and Nathalie Reuter ¹

Department of biological sceinces and Computational biology unit, University of Bergen
1. Department of Chemistry and Computational biology unit, University of Bergen

Membrane binding of peripheral proteins is governed by contributions from the partitioning of individual amino acids and from specific interactions with the lipids. Dissecting these individual amino acid contributions is challenging from equilibrium molecular dynamics simulations. On the other hand, methods like free energy of perturbation (FEP) can be used in principle to evaluate these contributions by mutating residues involved in binding. In this work, we use FEP to quantify the role of aromatics in the affinity of Bacillus thuringiensis phosphatidylinositol-specific phospholipase C (BtPI-PLC), phospholipase A2 (PLA2) from venom of the cobra (Naja naja atra) and Neutrophil serine proteases Proteinase 3 (PR3) for phosphatidylcholine-containing bilayers. We selected aromatic amino acids located at various positions in the interfacial binding sites of these peripheral proteins and mutated them to alanine to evaluate their contributions in membrane binding. Earlier computational and experimental work identified some of the tyrosines to mediate cation-Ï€ interactions with choline groups from the phospholipids, and others to partition at the interface without mediating cation- Ï€ interactions in BtPI-PLC. The cation-Ï€ interactions are less evident for tryptophan and phenylalanine. The FEP results show significantly different contributions for the aromatics involved in the cation-Ï€ interactions than those without cation-Ï€ interactions but partitioning in the head group region. Tyrosine and phenylalanine contribute favorably around 1.0 Kcal/mol when partitioned at the phosphate plane and this contribution increase to (2.0 - 2.5 )Kcal/mol and (2.5 - 3.0) Kcal/mol respectively when mediating cation-Ï€ interactions. The contribution from tryptophan is more favorable (around 2.0 Kcal/mol) due to its bigger size when partitioned at the phosphate plane and increases with the depth of insertion to reach the same value as for cation-Ï€ interactions where it contribute 3.0 â€“ 3.5 Kcal/mol. Our results are in good agreement with available experimental data and in particular with the measured changes in the equilibrium dissociation constants of the mutant compared to the wild type protein.

KM19

Is Your Mechanism Correct?

Kathrin H. Hopmann

Hylleraas Centre for Quantum Molecular Sciences, Dept. of Chemistry,
UiT- The Arctic University of Norway, N-9037 Tromsø, Norway

Email: kathrin.hopmann@uit.no, Web: site.uit.no/CHOCO

Reaction pathways and properties of relatively large chemical systems can nowadays be modelled with reasonable speed and good accuracies [1,2]. However, mechanistic computations are often based on model substrates, and the proposed pathways are not always validated against known experimental information. Here I will show how the computation of known selectivities of real substrates can help to establish the validity of proposed mechanisms [3,4].

Left: Current computational methods are able to treat realistic systems with good accuracies (from ref. 1a). Right: Computationally proposed mechanisms require verification to ensure the validity.

References

a) K. H. Hopmann, How accurate is DFT for iridium-mediated chemistry, Organometallics 2016, 35, 3795, b) K.H. Hopmann, Quantum chemical studies of asymmetric reactions: Historical aspects and recent examples, Int. J. Quantum Chem. 2015, 115, 1232.
K. H. Hopmann, Iron-Brønsted-acid-catalysed asymmetric hydrogenation: Mechanism and selectivity-determining interactions, Chem. Eur. J. 2015, 21, 10020.
G. R. Morello, H. Zhong, P. J. Chirik, K. H. Hopmann, Cobalt-catalysed alkene hydrogenation: A metallacycle can explain the hydroxyl activating effect and the diastereoselectivity, Chem. Sci. 2018, In Press.
G. R. Morello, K. H. Hopmann, A dihydride mechanism can explain the intriguing substrate selectivity of iron-PNP-mediated hydrogenation, ACS Catal. 2017, 7, 5847.

KM20

Computational insights into the decomposition pathways of Ru-based olefin metathesis catalysts

Marco Foscato, Wietse Smit ,Giovanni Occhipinti, Vidar R. Jensen

Department of Chemistry, University of Bergen, Norway

Olefin metathesis is â€œone of organic chemistryâ€™s most important reactionsâ€ and the development of such fundamental tool granted the Nobel Prize in Chemistry for 2005.^[1] In this reaction a transition metal complex catalyzes the formation of carbon-carbon double bonds between two alkene substrates making the synthesis of complex olefins â€œsimple to use (stable in air), efficient, and environmental friendly.â€^[1]

However, despite these promises, implementations of olefin metathesis processes in the pharmaceutical industry highlight low productivity as a major challenge.^[2] Drug synthons are, in fact, usually highly functionalized molecules often characterized by polar and acid-base groups that trigger catalyst decomposition.

To gain the insight necessary to understand and prevent catalyst decomposition, we investigated the reaction network of one of the most popular Ru-catalyst for olefin metathesis (Hoveyda-Grubbsâ€™s second generation catalyst). Computational studies and experiments allowed the exploration of the complicated reaction network that surrounds the known olefin metathesis reaction mechanism. The identification of a pivotal decomposition intermediate led to the discovery of reaction pathways transforming the metathesis catalyst into the deleterious olefin isomerization catalyst.^[3] Moreover, deprotonation of the metallacyclobutane species, which is the key intermediate in olefin metathesis, could explain the reduction of turnovers in presence of Brønsted base,^[4] and bimolecular coupling of two Ru-alkylidenes was also shown to generate metathesis inactive species.^[5]

This knowledge clarifies the weaknesses of the vulnerable species involved in productive olefin metathesis reaction, and provides the basis for catalyst redesign.

References

The Nobel Prize in Chemistry 2005. NobelPrize.org. Nobel Media AB 2018. https://www.nobelprize.org/prizes/chemistry/2005/summary
C. S. Higman, J. A. M. Lummiss , D. E. Fogg, Angew. Chem. Int. Ed. 2016, 55, 3552-3565.
J. Engel, W. Smit, M. Foscato, G. Occhipinti, K. W. Törnroos , V. R. Jensen, J. Am. Chem. Soc. 2017, 139, 16609-16619.
G. A. Bailey, J. A. M. Lummiss, M. Foscato, G. Occhipinti, R. McDonald, V. R. Jensen , D. E. Fogg, J. Am. Chem. Soc. 2017, 139, 16446-16449.
G. A. Bailey, M. Foscato, C. S. Higman, C. S. Day, V. R. Jensen , D. E. Fogg, J. Am. Chem. Soc. 2018, 140, 6931-6944.

KM21

Platform for Ontology Engineering and Evolution for Nano and Quantum Technologies

Axel Peter MUSTAD, Keeper Layne SHARKEY

Nordic Quantum Computing Group AS (NQCG), Oslo, Norway

Active direct communication with a uniquely recognizable language is fundamental to knowledge transfer [1] between humanistic entities. Building a standardized community with an expert level understanding of rules for organizational classes of things, e.g., complex functional nano-materials [2], quantum circuit protocols [3] from the emerging field of quantum information theory, to the creation of various plasmas [4], or even reinventing the shape of the periodic table of the elements [5], is achieved by creating an effective ontology. The agreed nomenclature is key to the growth of a healthy economic and scientific sector as demonstrated by International Union for Pure and Applied Chemistry (IUPAC) for the chemical industry starting in the early 1900’s [6] through the Gene Ontology Consortium in the 21st century [7]. Integrating an ontology and managing it is a critical step in increasing humans’ ability to solve advanced questions and problems with a continually growing complexity; for instance, disease discovery and verification in the medical field [8]. Through advanced algorithms and artificial intelligence new ontologies have been achieved by quantifying vast amounts of data and information. Nordic Quantum Computing Group (NQCG) [9] has been directly involved with coalescing nano-specific data sources [10].

Realizing a nano- and quantum-specific ontology (NaQuOnt) is central to the mission of NQCG which aims to enable participation by forming strategic partnerships with various academic and private establishments globally to provide an open-source Software as a Service (SaaS). NQCG’s core activity proposal is to engineer the implementation of a suitable, web-based browsing tool that acts as a communication forum and exploits machine learning with the use of Web Ontology Language (OWL2), a standard language for data processing of the World Wide Web Consortium (W3C) [11], in conjunction with Stanford’s Protégé [12]. Validation of the NaQuOnt requires interaction with leading researchers and innovators in the field; current partners includes Google [13] and their development of quantum computing capabilities allows for NQCG’s experimentation. To emphasis, current quantum computing technologies are accelerating computational quantum chemistry and will impact new material discoveries and properties [14] which will directly impact the need for said ontology. Integration of applications and software systems for the resulting ontological capabilities is implemented across global industry value chains in technology partnership with SAP’s enterprise resources planning management systems [15]. Industry-quality ontology standards created by NQCG and partners will further promote global safety and compliance regulation, including risk analysis of the developed technologies and consequently accelerating the maturation of the technologies and the human experience of quantum chemistry.

References:

Jasimuddin, S. M. and Zhang, Z. J. Operational Research Soc. 60, 706-716 (2009)
Himanen, L., et. al., Computational Materials 4, 52 (2018)
Pino, H., et. al., Quantum Science and Technology 3, 025001 (2018)
Stockman, M., et. al. J. Opt 20, 043001 (2018)
Grochala, W. Foundational Chemistry 20,191-207 (2018)
https://iupac.org/
http://www.geneontology.org/
https://www.snomed.org
http://nqcg.com/
Karcher, S., et. al. NanoImpact 9, 85-101 (2017)
https://www.w3.org/TR/owl2-overview/
https://protege.stanford.edu/
https://ai.google/research/teams/applied-science/quantum-ai/
Reiher, M. et. al. PNAS 114, 7555-7560 (2017)
https://www.sap.com/index.html

MK - Makromolekyl- og kolloidkjemi

MK1

Nanoparticle delivery systems for antimicrobial peptides

Martin Malmsten

Department of Pharmacy, University of Copenhagen, DK-2100 Copenhagen, Denmark,
Department of Pharmacy, Uppsala University, P.O. Box 580, SE-752 32 Uppsala, Sweden

Presenting author email: martin.malmsten@sund.ku.dk

Due to rapidly increasing resistance development against conventional antibiotics, finding novel approaches for the treatment of infections has emerged as a major health issue. Antimicrobial peptides (AMPs) have attracted interest in this context, and there is by now a considerable literature on the identification such peptides, as well as on their optimization to reach potent antimicrobial and anti-inflammatory effects at simultaneously low toxicity against human cells. In comparison, delivery systems for antimicrobial peptides have attracted considerably less interest. However, such delivery systems are likely to play a key role in the development of potent and safe AMP-based therapeutics, e.g., through reducing chemical or biological degradation of AMPs either in the formulation or after administration, by reducing adverse side-effects, by controlling AMP release rate, by promoting biofilm penetration, or through achieving co-localization with intracellular pathogens.

Here, an overview is provided of some of our recent work on delivery systems for antimicrobial peptides, including polymer nanogels[1,2], mesoporous silica[3], nanoclays/nanosheets[4], and quantum dots, with special focus on AMP-carrier interactions, as well as consequences of these for membrane interactions, as well as for antimicrobial and related biological effects of AMP-containing formulations.

Figure 1. Nanoparticulate drug delivery systems provide various advantages for antimicrobial peptides.

References

R. Nordström, R., et al. J. Colloid Interface Sci. 2018, 513, 141.
S. Singh, et al., ACS Appl. Mater. Interfaces 2017, 9, 40094.
K. Braun, et al. J. Colloid Interface Sci. 2016, 475, 161.
S. Malekkhaiat Häffner, et al. Phys. Chem. Chem. Phys. 2017, 19, 23832.

MK2

Microencapsulation and Controlled Release of Active Ingredients in Food, Feed and Personal Care Products.

Wilhelm R. Glomm, Peter Molesworth, Eugenia Sandru, Le Thuy Truong, Ruth Schmid, Heidi Johnsen

Polymer Particles and Surface Chemistry Research Group, Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway

Correspondence: wilhelm.glomm@sintef.no

Microencapsulation is a process whereby an active ingredient – gas, liquid or solid – is wrapped within a polymeric coating, forming small particles, typically in the micrometer range. The polymer acts as a barrier, isolating and protecting the active ingredient from the external environment, and can dissolve or disintegrate through specific stimulus, releasing the microcapsule content under specified conditions. Depending on the active ingredient and the intended application, microencapsulation is used to protect sensitive ingredients such as vitamins from oxidation, increase solubility/compatibility, mask unwanted taste and smell, increase bioavailability, promote gradual or triggered release and more.

The Polymer Particles and Surface Chemistry Research Group at SINTEF Industry is working with tailored encapsulation and release for a range of applications and markets, using methods such as interfacial polymerization, spray drying and complex coacervation. In this talk, requirements for matching wall materials, microencapsulation method and release profile will be discussed for several active ingredients used in food, feed and personal care products.

MK3

Ultrafast DNA sequencing enabled by novel Ugelstad bead technology.

Synne Larsen(a), Geir Fonnum(a), Talha Gökmen(a), Maarten Bruinsma(a), Lene Husabø(a), Nini Hofsløkken Kjus(a), Grete Modahl(a), Astrid Molteberg(a), Wolfgang Hinz(b), Prasanna Thwar(c)

a)    Svelleveien 29, 2004 Lillestrøm, Norge
b)    246 Goose Lane, Guilford, CT, 06437, USA
c)    180 Oyster Point South San Francisco, CA 94080 USA

E-mail: Synne.larsen@thermofisher.com

DNA sequencing has become a disruptive tool in human diagnostics. However, the high cost delayed and almost excluded the method to be used in healthcare. Ion Torrent (part of Thermo Fisher Scientific) has developed a next generation sequencing (NGS) method where their semiconductor technology enables massive parallel sequencing, thereby solving the cost challenge.

The actual sequencing occurs in a semiconductor chip, with millions of micro-sized wells. The presence of one hydrogel bead in each well are crucial for anchoring the genetic material within the wells. Nucleotides are flooded over the chip and binds to the unpaired nucleotides on the single stranded DNA on the bead. When a nucleotide binds, a proton is released and gives a positive signal. Ion Torrent were successful in the solution, but lacked a bead technology to secure the required number of DNA in each well.

The beads must be highly monodisperse, with a tailor-made matrix that is compatible with DNA and PCR. The talk will present how Thermo Fisher Scientific Norway developed a novel seeded polymerization process for custom-production of hydrogel beads for Ion Torrent, utilizing Ugelstad technology. The traditional Ugelstad technology is limited to organic soluble monomers, thus resulting in hydrophobic beads. To be able to make not only hydrophilic, but hydrogel beads, new innovative solutions were required.

Today Ion Torrent sequencers are the second most used sequencing platform in the world and number one in oncology. The invention of the tailor-made hydrogel beads was awarded both the Norwegian Research Council Innovation Award and the Norwegian Tech Award in 2017.

MK4

Polymer films as matrix in drug delivery systems.

Ingunn Tho

School of Pharmacy, University of Oslo, Norway
Email: Ingunn.tho@farmasi.uio.no

Oral wafers or orodispersible films have become popular as drug delivery systems, since they offer an alternative way to administer drugs by melting or dispersing rapidly on the tongue without additional water. Other types of film formulations are mucoadhesive systems that will stick to the mucosa assuring prolonged contact time, which can be utilized to improve absorption of the drug across the mucosa, either the buccal mucosa, vaginal mucosa or intestinal mucosa.

Orodispersible films are usually prepared by the solvent-casting method from a viscous polymer solution of a water-soluble polymer, such as hydroxypropyl methylcellulose (HPMC), pullulan, starch or polyvinyl pyrrolidone (PVP). The dry film is formed upon evaporation of the solvent. In more advanced systems, the polymer film serve as a matrix for nanoparticles, whose purpose might be to solubilize poorly soluble drug, control the drug release, stabilize instable drugs or simply mask the bitter taste of the drug. A few additional excipients are added to the formulation in order to make it more palatable and patient friendly. Typically, a plasticizer (e.g. glycerol, PEG), an aroma and/or a sweetener and sometimes a filler to increase the content of solid material in the dry film.

We work with various types of film formulations with and without nanoparticles [e.g. 1-4], and some recent examples will be discussed in the presentation.

References

L.Roque, et al., Eur. Polym. J. 104 (2018) 19-31
L.Roque, et al., Bioinspir. Biomim. 13 (2018) 055001
J.Alopaeus et al., 2018 (submitted)
J.Alopaeus et al. 2018 (in preparation)

MK5

Role of protein self-association on DNA condensation and nucleoid stabilization in a bacterial cell model

Rita S. Dias

Department of Physics, NTNU Norwegian University of Science and Technology, Trondheim, Norway

Bacterial cells do not have a nuclear membrane that encompasses and isolates the genetic material. In addition, they do not possess histone proteins, which are responsible for the first levels of genome condensation in eukaryotes. Instead, DNA condensation in bacterial cells is driven (at least partially) by DNA-binding proteins and macromolecular crowding. Yet, some of these proteins also bind to RNA, a component of ribosomes, which are present in large concentrations in the cytosol of the cells.

In this work we use Monte Carlo simulations and a simple coarse-grained bacterial cell model, enclosing a (bead and spring) model DNA, protein dimers and crowding agents, to study the role of protein self-association (a characteristic that some protein classes possess) on DNA condensation and on the stability of the DNA-protein complex, towards protein-competitive binding to the crowding agents. The results of the simulations are in good agreement with exclusion dye experiments conducted to probe synergism and competition effects of DNA condensation by binding agents in the presence of crowding agents with different characteristics.

MK6

On the Cooperativity during Melting and Molecular Exchange in Micelles with Crystalline Cores

Nico König, Lutz Willner, and Reidar Lund

Departmewnt of Chemistry, University of Oslo

Molecular exchange processes are important equilibration and transport mechanisms in both synthetic and biological self-assembled systems such as micelles, vesicles and membranes. Still these processes are not entirely understood, in particular the effect of crystallinity and the interplay between cooperative melting processes and chain exchange. Here we focus on a set of well-defined polymer micelles formed by binary mixtures of poly(ethylene oxide)-mono-n-alkyl-ethers (Cn-PEO) which allows the melting point to be tuned over a wide range. We show that while the melting transition is cooperative in the confined 2-3 nm micellar core, the exchange process is widely decoupled and unimeric in nature. As confirmed by calorimetry (DSC), the total activation energy below the melting point is the sum of enthalpy of fusion, and the corresponding activation energy in the melt state. This suggests that while the crystallization process is cooperative, a "single chain melting process" preludes the molecular diffusion process during chain exchange.

MK7

Probing the Structure of Lipid Bilayers and their Interaction with Indolicidin using Small Angle X-ray and Neutron Reflectivity methods

Josefine Eilsø Nielsen, Victoria Ariel Bjørnestad, Abdullah Lone, Håvard Jenssen, Tania Kjellerup Lind, Marité Cardenas and Reidar Lund

Department of Chemistry, University of Oslo

Antibiotic resistance is one of the biggest threats to global health, according to WHO. AMPs seem to be able to evade much of the bacterial resistance mechanisms and are therefore promising candidates for future antibiotics. Instead of blocking specific biochemical pathways as most available antibiotic agents today, most AMPs act physically on the cytoplasmic membrane itself.[1-2] The precise microscopic mechanism for the disturbance of the membrane has not fully been proven but several theories has been suggested including membrane deformation and pore formation. Here we have used state of the art neutron and x-ray scattering techniques to investigate the microscopic mechanism of action of AMPs with model bacterial membranes. SAXS measurements on a model peptide, Indolicidin together with lipid vesicles has shown that Indolicidin interacts with the membrane. Based on analysis of the results we can see that the peptide does not seem to affect the structure of the bilayer significantly but situates in the interface between the lipid head group and the tail in the outer leaflet in the bilayer.[3] This causes and slight alteration in the lipid chain packing as seen by calorimetry but does not lead to any significant membrane thinning or similar. This is further confirmed by Neutron Reflectivity and Atomic Force Microscopy on planar supported bilayers.[4] Combining these techniques has given us a new important insight into how the peptide interact with the bilayer. Rather than supporting any specific structural model, we speculate that the mechanism is compatible with the disordered model proposed by Wimley.[5]

References

Hancock, R. E.; Rozek, A., FEMS microbiology letters 2002, 206 (2), 143-149.
Jenssen, H.; Hamill, P.; Hancock, R. E., Clinical microbiology reviews 2006, 19 (3), 491-511.
Nielsen, J. E.; Bjørnestad, V. A.; Lund, R., 2018, (in preparation)
Nielsen, J. E.; Bjørnestad, V. A.; Lone, A.; Lind, T. K.; Jenssen, H.; Cardenas, M; Lund, R., 2018, (in preparation)
Wimley, W. C., ACS chemical biology 2010, 5 (10), 905-917."

MK8

Living apart together: tuning supramolecular assembly to create functional nanostructured soft materials.

Christian Sproncken, Hande Cingil, Antonio Aloi, Neus Vilanova, Isja de Feijter, Gijs ter Huurne, Martijn Gillissen, Lafayette de Windt, Anja Palmans, Bert Meijer, Ilja Voets

TU- Eindhoven, NL

Self-organization provides a fast, efficient, and low-cost pathway to functional and responsive hierarchically structured materials that are difficult if not impossible to prepare by other means. I will focus on our recent work in this area, wherein we develop novel approaches to achieve a high level of control over intra- and interparticle interactions to modulate assembly pathways and precisely direct the microstructure and properties of the final material [1-10] targeting temporally programmable assembly [9] and novel applications [10].

First, I will discuss how the hydrogen-bond driven assembly in solution of C3-symmetrical discotics based on benzene-1,3,5-tricarboxamides (BTAs) can be utilized to prepare a wide range of nanostructured materials [1-5], ranging from stiff, helical, one-dimensional fibers [1] to photosensitive Pickering emulsions stabilized by supramolecular colloids [6-7]. I will showcase how (macro)molecular structure and physico-chemical factors impact the hierarchical organisation of the materials [4-5], which is crucial to further their application potential in catalysis, sensing, drug delivery, and coating technology.

Second, I will address electrostatically driven assembly of block copolymers into so-called complex coacervate core micelles (C3Ms) composed of a mixed core of polyelectrolyte blocks and a corona consisting of neutral solvent-swollen blocks [8-10]. Interestingly, C3Ms are multi-responsive nanostructures that readily adapt to changes in charge stoichiometry, pH, ionic strength, as well as external cues, like temperature and light, provided suitable (co)polymers are selected. An overview will be presented of recent work on various types of C3Ms developed for specific biomedical and materials science applications demonstrating e.g. temporally programmed association and cargo release [9], as well as inhibition of ice recrystallization [10].

References

Gillissen, M. A. J.; Koenigs, M. M. E.; Spiering, A. J. H.; Vekemans, J. A. J. M.; Palmans, A. R. A.; Voets, I. K.; Meijer, E. W. JACS, 2014, 136, 336.
M. A. J. Gillissen, T. Terashima, E. W. Meijer, A. R. A. Palmans and I. K. Voets Macromolecules, 2013, 46, 4120.
P. J. M. Stals, M. A. J. Gillissen, T. F. E. Paffen, T. F. A. de Greef, P. Lindner, E. W. Meijer, A. R. A. Palmans, and I. K. Voets Macromolecules, 2014, 47, 2947.
G. M. ter Huurne, M. A. J. Gillissen, A. R. A. Palmans, I. K. Voets and E. W. Meijer Macromolecules, 2015, 48, 3949.
Ter Huurne, G. M.; de Windt, L. N. J.; Liu, Y.; Meijer, E. W.; Voets I. K.; Palmans, A. R. A. Macromolecules 2017, 50, 8562-8569
I. de Feijter, L. Albertazzi, A. R. A. Palmans, I. K. Voets, Langmuir, 2015, 31, 57.
N. Vilanova, I. de Feijter, A. J. P. Teunissen and I. K. Voets, Nature Scientific Reports, 2018, 8, 1271.
A. Aloi, C. Guibert, L. L. C. Olijve, I. K. Voets, Polymer, 2016, 107, 450
H. E. Cingil, N. C. H. Meertens and I. K. Voets Small, 2018, 1802089, 1.
C. C. M. Sproncken, R. Surís-Valls, H. E. Cingil, C. Detrembleur, I. K. Voets, Macromol. Rapid Commun., 2018, 39, DOI: 10.1002/marc.201700814

MK9

Lipid nanotubes: a possible route to protocell formation and growth

Elif Senem Koksal, Susanne Liese, Ilayda Kantarci, Ragni Olsson, Andreas Carlson, Irep Gözen

University of Oslo

Membrane-enclosed cellular compartments create spatially distinct microenvironments which confine and protect biochemical reactions in the cell. On the early Earth, the autonomous formation of compartments is presumed to have enabled encapsulation of nucleotides, satisfying a starting condition for the emergence of life. Recently, surfaces have become into focus as potential platforms for the self-assembly of prebiotic compartments, as notably enhanced vesicle formation was reported in the presence of solid interfaces. The detailed mechanism of such formation at the mesoscale however is still under discussion.

Here we report on the spontaneous transformation of lipid reservoirs on solid substrates to unilamellar membrane compartments through a sequence of topological changes, proceeding via a network of interconnected lipid nanotubes. We show that this transformation is entirely driven by surface-free energy minimization and does not require hydrolysis of organic molecules, or external stimuli such as electrical currents or mechanical agitation. The vesicles grow by taking up the external fluid environment, and can subsequently separate and migrate upon exposure to hydrodynamic flow. This may explain, for the first time, the details of self-directed transition from weakly organized bioamphiphile assemblies on solid surfaces to protocells with secluded internal contents.

MK10

Applied colloid chemistry - research in an industrial setting

Rolf Andreas Lauten

Borregaard

Dispersants and/or viscosity modifiers is one of the major application areas for some of the chemicals produced at the Borregaard Biorefinery in Sarpsborg. For development of existing and new application areas, an understanding of the requirements in both the end application, but also physical characteristics of the dispersants themselves are important. The latter can be a challenge for a poorly defined natural polymer. Examples illustrating the use within cement chemistry and gold leaching will be given and discussed in relation to dispersant characteristics.

MK11

Paint is not just paint – Protective coatings for the wind power industry.

Jacob Stensgaard Diget

Jotun A/S

Jotun, a paint supplier with over 10,000 employees world-wide, are expanding their portfolio to protective coatings for wind-turbine rotor blades. The work associated with the development of a protective coating for the leading edge of a wind turbine rotor blade will be presented. The leading edge is exposed to some of the harshest environments with raindrop impingement at rotor blade tip speed of up to 500 km/hr. To withstand this, a special binder system (polymer network) is needed along with a “perfect” (smooth and void free) surface.

MK12

Multifunctional Nanomaterials – at the junction of polymer science and colloid chemistry.

Sulalit Bandyopadhyay, Jibin Antony, Karthik Raghunathan, Anuvansh Sharma

NTNU

The interdisciplinary nature of nanoscience has shown that combination results in unprecedented nanomaterial properties that not only represent that of the counterparts but exceed them. This has made synthesis and properties optimization of polymer based nanomaterials a fascinating field that requires knowledge at the intersection of polymer science and colloidal chemistry. Such nanomaterials are capable of performing multiple functions, for instance; respond to stimuli, encapsulate cargo molecule, release cargo molecule in a controlled fashion - all from a single platform. However, when it comes to combination of two different kinds of nanomaterials, the emergent nanomaterial loses potential in its desired applicability.

Here, we will discuss how concepts borrowed from surface and colloid chemistry may be used to control the physico-chemical properties of metallic nanoparticles (NPs) synthesized via thermal decomposition method (Fe NPs) and solution based seeded-growth method (Au NPs). Thereafter, the effect of varying reaction parameters such as mole ratios of monomers, surfactant concentration on the physico-chemical properties of poly(N-isopropyl-acrylamide) (pNIPAm) based hydrogels will be discussed. One manifestation of combination of such hydrogels and metallic NPs will be highlighted in drug delivery applications. Tuning the release of active cargo depends not only on material properties but also on the effect of external stimuli such as temperature, pH and so on. The potential of such smart nanomaterials will be shown in other environmental applications such as in hydrological tracing, water management and others. The end-use of such multifunctional nanomaterials depends on modulation of their physico-chemical properties that rests back on knowledge utilization of synthesis and functionalization.

MA - Matkjemi

MA1

Fisk, oppdrettsfisk og helse.

Helle Katrine Knutsen

Avdeling for Miljøeksponering og –epidemiologi, Folkehelseinstituttet, Oslo

Abstract mangler.

MA2

Overvåkningsprogrammer for oppdrettsfisk.

Rita Hannisdal

Avdeling Sjømat i Modellsystem, Havforskningsinstituttet, Bergen

Abstract mangler.

MA3

Hvordan skal vi forholde oss til at kjemiske analysemetoder blir stadig mer følsomme?

Gjermund Vogt

Fagsjef Kjemi, Eurofins Norge, Moss

Abstract mangler.

MA4

Fate of the antioxidant ethoxyquin from feed to salmon filet: application of liquid chromatography coupled to ion mobility and high resolution mass spectrometry.

Sylvain Merel

Avdeling Trygt Fôr, Havforskningsinstituttet, Bergen

Ethoxyquin is commonly present in fish feed and acts as an antioxidant. The quick oxidation of ethoxyquin prevents the oxidation of other components responsible for the nutritional quality of the feed. Identifying the transformation products of ethoxyquin and examining their occurrence and transfer from fish feed to salmon filet is important for risk assessment purposes. Previous research relying on chemical bench-scale oxidation and the analysis of fish feed allowed identifying 37 transformation products of ethoxyquin. Therefore, this study aimed at extending the current knowledge to the identification of transformation products in fish muscle.

To achieve this objective, salmons were fed during 90 days with fortified feed containing ethoxyquin at 0.5 mg/kg, 119 mg/kg, and 1173 mg/kg. In addition, the occurrence of ethoxyquin and its transformation products was also assessed in fillets from 12 commercial Norwegian farmed salmon. All salmon filets were extracted in acetonitrile and analyzed by liquid chromatography with travelingwave ion mobility spectrometry coupled to high resolution mass spectrometry. Salmon filets from the feeding trial showed the occurrence of ethoxyquin along with 23 transformation products resulting from dimerization, oxygenation,cleavage, cleavage combined with oxygenation, cleavage combined with conjugation, and other alterations. Among them, 10 were characterized for the first time. In filets of farmed salmon intended for human consumption, ethoxyquin was detected in 75% of the samples. In addition, 24 transformation products were also detected with a frequency ranging from 8% to 100%. In all salmon filets from both the feeding trial and fish farms, transformation products resulting from dimerization were by far the most abundant. In particular, the ethoxyquin dimer 1,8-EQDM was the main transformation product.

Finally, ion mobility spectrometry provided additional confidence for compound identification during screening analysis. In complex matrices or when the abundance is too low to allow the detection of characteristic fragments, collision cross section with a 2% deviation lowers potential interferences and false positives. The current study allowed a comprehensive knowledge of the fate of ethoxyquin from fish feed to salmon filet, and brought the total number of transformation products identified to 47.

MA5

Miljøeffekter av kjemikalier brukt mot lakselus.

Renée Katrin Bechmann

IRIS, Stavanger

Lakselus er et problem for fiskehelsen. Selv om oppdrettsnæringen bruker ulike metoder for å hindre at laks får lus, brukes det fremdeles betydelige mengder kjemikalier som medisin. Laksen blir behandlet enten med medisinfôr som inneholder pesticider, eller det tilsettes kjemikalier i vannet for å bli kvitt lus. Rester av medisinfôr eller kjemikalier fra badebehandling i merden eller i brønnbåt slippes rett ut i havet. Kanskje blir miljøet bare utsatt for kjemikaliene en kort stund, men i områder med oppdrett kan krepsdyr og andre organismer utsettes for et eller flere kjemikalier flere ganger. Målet i PestPuls prosjektet er å skaffe ny kunnskap om hvordan den viktige dypvannsreka Pandalus borealis kan påvirkes av kjemikalier brukt i badebehandling av laks. Det er viktig å finne ut hvor følsom dypvannsreka er for kjemikalier som slippes ut fra oppdrettsnæringen, siden den er en nøkkelart i økosystemet og spises både av fisk og folk. Vi har sjekket hvordan korte, gjentatte eksponeringer for AlphaMax (deltametrin) og Salmosan (azametifos) alene og i kombinasjon påvirker rekene.

AlphaMax behandlingsløsning for laks inneholder 2 mikrogram deltametrin per liter. Tusen ganger fortynnet (2 ng/L deltametrin) løsning drepte voksne reker på mindre enn ett døgn. Da rekene ble eksponert kun to timer per dag i en uke overlevde de, men de spiste betydelig mindre enn kontrollen og det var skade på vevet i fordøyelseskjertelen. Eksponering for titusen ganger fortynnet løsning i ett døgn ga endringer i adferd, men ingen dødelighet. Rekelarvene var enda mer følsomme for AlphaMax enn de voksne rekene. Det var høy dødelighet etter to timer med 2 ng/L, og få av de som overlevde klarte å svømme.

Salmosan behandlingsløsning for laks inneholder 100 mikrogram azametifos per liter. Det var ingen dødelighet av voksne reker som ble eksponert i ett døgn for tusen ganger fortynnet løsning (100 ng/L), og heller ingen dødelighet etter to timers eksponering per dag i en uke, men det var skade på vevet i fordøyelseskjertelen. Det var ingen tydelig effekt på overlevelse for rekelarver utsatt for 100 ng/L i to timer. Reker utsatt for både Salmosan og AlphaMax hadde lignende responser som de som kun fikk AlphaMax, men det var mer skade på fordøyelseskjertelen til voksne reker i den kombinerte eksponeringen.

Paramove behandlingsløsning for laks inneholder 1500 mg/L hydrogen peroksid. Økt dødelighet og redusert spiserate ble observert for voksne reker etter eksponering for tre to-timers pulser med 1.5 mg/L. Økt dødelighet ble også observert etter kun to timers eksponering for 15 mg/L. Dødeligheten skjedde omtrent tre dager etter eksponeringen (forsinket effekt). Tydelige skader på gjellene og lipid peroksidering i fordøyelseskjertelen ble funnet etter en times eksponering for 1.5 mg/L og 15 mg/L hydrogen peroksid. Hovedkonklusjonen er at få timers eksponering for AlphaMax eller Paramove førte til økt dødelighet av reker selv ved tusen ganger lavere konsentrasjon enn det som brukes til å behandle laksen.

PestPuls ledes av NORCE med NIVA (kjemi og modellering), Universitetet i Leicester (genekspresjon), DEBtox Research (modellering) og Burridge Consulting Inc. som partnere, i tillegg til en nasjonal rådgivningsgruppe med representanter fra forvaltning, fiskeri og oppdrett. Dette foredraget vil fokusere på effekter på rekene i forsøk utført av NORCE i 2017 og 2018.

OR - Organisk kjemi

OR1

Harnessing Nature's Toolbox for Selective Halogenations: New Concepts for an Old Problem.

Tanja Gulder

Biomimetic Catalysis, Department of Chemistry and Catalysis Research Center, Technical University Munich, Lichtenbergstrasse 4, 85748 Garching, Germany.

Email: Tanja.Gulder@tum.de

Although the halogenation of organic molecules is one of the most widespread techniques for the functionalization of substrates, efficient catalytic methods for the selective (regio-, chemo-, and in particular stereoselective) construction of carbon-halogen bonds are rare. In contrast, Nature has evolved different strategies to create carbon-halogen bonds in a highly effective and specific manner.

Our research therefore focuses on the exploration of the mechanism as well as the structure-function relationship of such halogenation catalyzing enzymes. Based on these findings mild, generally applicable, and selective catalytic methods for the formation of carbon-halogen bonds (brominations, chlorinations and even fluorinations) are developed combined with their application to access medically relevant target structures in efficient ways. Selected examples of our group imitating Nature’s concepts of halogenation reactions will be presented, reaching from biotransformation [1] to λ³-iodane [2] and amine[3] mediated transformations.

References

a) Frank, A.; Seel, C. J.; Groll, M.; Gulder, T. ChemBioChem 2016, 17, 2028; b) C. J. Seel; A. Králík, M. H., A. Frank, B. Koenig, T. Gulder ChemCatChem 2018, online available, doi.org/10.1002/cctc.201800886
a) Fabry, D. C.; Stodulski, M.; Hoerner, S.; Gulder, T. Chem. Eur. J. 2012, 18, 10834; b) Stodulski, M.; Goetzinger, A.; Kohlhepp, S. V.; Gulder, T. Chem. Commun. 2014, 50, 3435; c) Ulmer, A.; Stodulski, M.; Kohlhepp, S. V.; Patzelt, C.; Poethig, A.; Bettray, W.; Gulder, T. Chem. Eur. J. 2015, 21, 1444; d) Ulmer, A.; Brunner, C.; Arnold, A. M.; Poethig, A.; Gulder, T. Chem. Eur. J. 2016, 22, 3660; e) Arnold, A. M.; Ulmer, A.; Gulder, T., Chem. Eur. J. 2016, 22, 8728; f) Kohlhepp, S. V.; Gulder, T. Chem. Soc. Rev. 2016, 45, 6270; g) Patzelt, C.; Poethig, A.; Gulder, T. Org. Lett. 2016, 18, 3466; h) Brunner, C.; Andries-Ulmer, A.; Kiefl, G. M.; Gulder, T. Eur. J. Org. Chem. 2018, 2615; i) Andries-Ulmer, A.; Brunner, C.; Rehbein, J.; Gulder, T. J. Am. Chem. Soc. 2018, accepted.
A. M. Arnold, A. P., M. Drees, T. Gulder J. Am. Chem. Soc. 2018, 140, 4344.

OR2

Catalytic Approaches for Simplifying Complex Molecule Synthesis

Darren J. Dixon

Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK

Email: (darren.dixon@chem.ox.ac.uk)

Catalysts that provide new reactivity and stereocontrol in efficient bond-forming reactions, are essential tools for converting low cost starting materials into high value, structurally complex, stereochemically defined product materials. In this presentation, new families of metal-free and metal-rich cooperative catalysts and their use in highly enantioselective C-C bond forming reactions and other relevant transformations, will be described.

Their strategic application to the discovery of new one-pot reaction cascade processes to generate novel, stereochemically defined scaffolds and architectures useful for library and target synthesis will also be discussed. Further application of selected methodologies as pivotal carbon-carbon bond forming steps in the total synthesis of a range of manzamine, aspidosperma, iboga, strychnos and daphniphyllum alkaloids will then be discussed. These syntheses serve to illustrate how complex molecular targets can be rapidly accessed when combinations of catalyst-controlled reactions, one-pot multistep procedures and powerful route-shortening cascades are designed into the overall synthetic sequence.[1-10]

References

F. Sladojevich, A. Trabocchi, A. Guarna, D. J. Dixon, J. Am. Chem. Soc. 2011, 133, 1710.
M. Yu, C. Wang, A. F. Kyle, P. Jakubec, D. J. Dixon, R. R. Schrock, A. H. Hoveyda, Nature, 2011, 479, 88.
P. Jakubec, A. Hawkins, W. Felzmann, D. J. Dixon, J. Am. Chem. Soc. 2012, 134, 17482.
M. G. Núñez, A. J. M. Farley, D. J. Dixon, J. Am. Chem. Soc. 2013 135, 16348.
I. Ortín, D. J. Dixon, Angew. Chem. Int. Ed. 2014, 53, 3462.
A. D. Gammack Yamagata, S. Datta, K. E. Jackson, L. Stegbauer, R. S. Paton, D. J. Dixon, Angew. Chem. Int. Ed. 2015, 54, 4899.
R. De La Campa, I. Ortín, D. J. Dixon, Angew. Chem. Int. Ed. 2015, 54, 4895.
A. J. M. Farley, C. Sandford, D. J. Dixon, J. Am. Chem. Soc. 2015, 137, 15992.
J. Yang, A. J. M. Farley, D. J. Dixon, Chemical Science, 2017, 8, 606.
P. W. Tan, J. Seayad, D. J. Dixon, Angew. Chem. Int. Ed. 2016, 55, 13436.

OR3

Concise total synthesis of (±)-dehaloperophoramidine

Peter Somfai

Center for Analysis and Synthesis, Department of Chemistry, Lund University, Box 124, 22100 Lund, Sweden

Email: peter.somfai@chem.lu.se

Perophoramidine and communesin F are structurally related indole alkaloids. Dehaloperophoramidine is synthetic analogue of perophoramidine lacking aromatic halogens. Our study towards the total synthesis of dehaloperophoramidine have led to the discovery of two novel domino processes that significantly improve the efficiency of the total synthesis. The first domino process encompasses four steps and resulted in the formation of ortho-amide. The second domino was discovered through a careful examination of the reactivity of ortho-amide, ultimately resulting in the target compound. The vicinal quaternary stereocenters was installed early in the synthesis by employing Overmanâ€™s samarium mediated reductive dialkyltion procedure. Herein is the total synthesis of dehaloperophoramidine in eight step and 23 % overall yield. In addition, our studies towards Strictamine and Cephalotaxine will also be discussed.

References

Popov, K.; Hoang, A.; Somfai, P. Angew. Chem. Int. Ed. 2016, 53, 1801.

UM - Uorganisk kjemi og materialkjemi

UM1

Defect chemistry of functional oxides and their interfaces

T. Bjørheim

University of Oslo

Defects affect and give rise to a wide range of functional properties in oxide ceramics. Li⁺, H⁺, O₂^- and H^- species enable macroscopic ionic transport while a variety of aliovalent ionic defects act as strong charge carrier traps. Higher-dimensional defects such as surfaces, grain boundaries, and interfaces, being both structurally and chemically different to their bulk counterparts, may similarly act as sinks for variety of charged defects, in turn leading to charge-imbalance and deviations from local electroneutrality in the form of space-charge regions. This contribution explores the fundamental driving forces of defect formation in functional oxides, and accumulation at interfaces, by introducing the concepts of lattice site basicity and ion affinities and show how these properties can be determined from first principles calculations. The concept is applied to hydration of proton conducting oxides, showing how the oxides’ chemistry affect the defect chemistry of both bulk materials, their interfaces, and of nanocomposites.

UM2

Bimetallic CoRe in APD silica aerogels for ammonia decomposition.

Karsten Granlund Kirste, Karina Mathisen, Laura Torrente Murciano^†, Dragos Stoian^¶, Said Laassiri‡, Justin Hargreaves‡.

*Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway.
^†University of Cambridge, UK.
^¶Swiss-Norwegian Beamlines, European Synchrotron Radiation Facility, Grenoble, France.
‡University of Glasgow, UK.

Corresponding author, email: karsten.g.kirste@ntnu.no

Silica aerogels are ultra-porous amorphous materials consisting of interconnected silica particles and mostly air. The silica matrix is porous and consisting of micro- and mesopores, have a high surface area, low thermal conductivity and exhibits interesting surface characteristics such as hydrophobicity [1, 2]. Deposition and formation of nanostructures in this 3D support may result in high dispersions. Growth limitations caused by the support can greatly affect both reducibility and reversibility of the metal phase, which will influence the reactivity and economy.[3, 4].

Production of hydrogen from ammonia is widely studied due to its high hydrogen content and relative ease of storage. Ammonia decomposition is favoured by metal supported on more or less porous carriers and for this purpose, bimetallic phases of cobalt and rhenium supported on silica aerogel have been synthesised through co-precipitation and then dried with the ambient pressure drying method (APD). A range of CoRe@aerogels were prepared and the activity towards ammonia decomposition depend greatly on total metal loading, Co/Re-ratio and annealing. In situ XAS reveal that reduction of both cobalt and rhenium occurs simultaneously during H2-treatment and over a lower temperature range (300-350°C) than their monometallic analogues, suggesting a synergistic effect occurs promoted by the 3D support.

The CoRe@aerogel have a high degree of Co-Re mixing with the major phase from EXAFS analysis during pre-treatment and ammonia decomposition being small Co-Re clusters (<1nm). Interestingly an increase in the he multiplicity of a Co-O/N shell is observed during ammonia decomposition indicative of surface adsorbed nitrogen or increased interaction with the support.

References:

S. D. Bhagat, Y.-H. Kim, K.-H. Suh, Y.-S. Ahn, J.-G. Yeo and J.-H. Han, Microporous and Mesoporous Materials, 2008, 112, 504-509.
J. Fricke and T. Tillotson, Thin Solid Films, 1997, 297, 212-223.
J. de Graaf, A. J. van Dillen, K. P. de Jong and D. C. Koningsberger, Journal of Catalysis, 2001, 203, 307-321.
D. B. Akolekar and S. K. Bhargava, Journal of Molecular Catalysis A: Chemical, 2005, 236, 77-86.

UM3

Performance of all-oxide thermoelectric generator enhanced by high-temperature interfacial chemistry.

N. Kanas, M. Bittner, T.D. Desissa, S.P. Singh, T. Norby, A. Feldhoff, T. Grande, K. Wiik, M.-A. Einarsrud

NTNU

Thermoelectric generators (TEGs) represent an important and promising technology enabling the direct conversion of heat to electric energy. The traditional TEGs are composed of metals and applications are limited to low and medium temperatures due oxidation and melting. For high-temperature applications in ambient atmosphere all-oxide TEGs represent an attractive approach, both due to their high stability and low environmental impact.

To utilize the advantages of oxides at high temperature, thermoelectric modules with direct p-n junction (Fig. 1a) was fabricated using p-type Ca₃Co₄O₉ (CCO) and n-type Ca_0.931MnO₃ (CMO). The processing was conducted by spark plasma co-sintering, using tape casted LaAlO₃ (insulator) in between the two conductors to partially separate them. A layer of a p-type Ca₃CoMnO₆ (CCMO) was formed at the interface between the p- and n-type materials during sintering. The CCMO-phase showed unusually high Seebeck coefficient, beneficial for the performance of the device.

In this contribution we will present our ceramic processing approach and discuss the high- temperature chemistry of the material system. The results from a successfully tested co-sintered TEG (Fig. 1 a and b) will be presented in more detail, and possible reasons for the unusually high power output will be discussed.

Fig. 1 a) Cross-section of the module with illustrated current and heat flow; b) Electrical power output of the module

UM4

Surface modification of Ta3N5 nanotubes as photocatalyst for photoelectrochemical water splitting.

Kaiqi Xu1, Athanasios Chatzitakis1, Ingvild Julie Thue Jensen2, Mathieu Grandcolas2, Truls Norby1*

(1) Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, FERMiO, Gaustadalléen 21, NO-0349 Oslo, Norway.
(2) SINTEF Industry, P.O. Box 124 Blindern, NO-0314 Oslo, Norway

*corresponding author truls.norby@kjemi.uio.no

Ta₃N₅ nanotubes (NTs) were obtained from nitridation of Ta₂O₅ NTs, which were grown directly on Ta foil through a 2-step anodization procedure. A “waggling” appearance close to the “mouth” of Ta₂O₅ NTs was observed, and after nitridation, a unique mesoporous structure appeared on the walls of the Ta₃N₅ NTs. With Co(OH)_x decoration, a photocurrent density as high as 2.3 mA/cm² (1.23 V vs. NHE) was reached under AM1.5G simulated solar light, however, the electrode suffered from photocorrosion. More stable photoelectrochemical (PEC) performance was achieved by first loading Co(OH)_x, followed by loading cobalt phosphate (Co-Pi) as double co-catalysts. The Co(OH)_x/Co-Pi double co-catalysts may act as a hole storage layer that slows down the photocorrosion caused by the accumulated holes on the surface of the electrode. Optimized parameters, e.g. tuned deposition time, can further enhance the PEC performance and stability. The accumulated hydrogen production will be measured and quantified.

Figure 1. a) SEM image of the “mouth” of Ta3N5 NTs, b) j-U curves of Ta3N5 NTs with different surface modification and c) chronoamperograms showing the performance stability of different Ta3N5 NTs surface modifications

Acknowledgement: Financial support from the Research Council of Norway (CO2BiOPEC project 250261) is acknowledged.

UM5

Can hydroxyl radicals travel far? Gas phase transport and detection after photocatalytic generation at TiO2 nanorods.

X. Sun, K. Xu, A. Chatzitakis, T. Norby*

Department of Chemistry, University of Oslo, SMN, FERMiO, Gaustadalléen 21, NO-0349 Oslo, Norway
Tel.: +47-22840654
truls.norby@kjemi.uio.no

The quality of indoor environment is of great importance as it can significantly improve the human health, comfort and productivity [1]. Reactive oxidising species (ROS) can keep our air clean because they can non-selectively oxidise a wide range of air contaminants. Hydroxyl radicals are among the strongest ROS in the atmosphere and devices that can efficiently produce them can become an important class of air-cleaning solutions. TiO₂ in the presence of water and UV light has a unique ability to produce hydroxyl radicals [2]. Here, TiO₂ nanorods (TNRs) are synthesised and used as the photocatalyst for hydroxyl radicals generation in a gas phase photoreactor, taking advantage of the water that is present in air. Therefore, air with controlled relative humidity (RH) levels is used as the water supply. The main aim is to study the effectiveness of the radicals as a function of RH, as well as the distance from a model pollutant. It is also of interest to quantify the amount of radicals that are photocatalytically produced, bearing in mind that such a system can become a commercial cleaning device. To achieve the above, we studied the remote decolourisation of a solid Methylene Blue (MB) film and the change in conductivity of an electrochemical sensor, based on polyaniline (PANI). We observed a remote decolourisation efficiency of 26% under 80% relative humidity when the photocatalyst was placed 0.5 cm away from the MB film. This efficiency was reduced to 19% when the distance increased to 3 cm. Moreover, a rate of 10¹² radical molecules per second were photocatalytically produced, which were calculated by the change in conductivity of the PANI sensor. Therefore, we hold it likely that hydroxyl radicals can travel far and generators with certain requirements can be developed.

Figure 1: Effect of UV light, photocatalyst (TNRs) and its distance from the MB at 80% RH. Airflow rate: 0.75 mL/min (a), digital image of a MB film used as the colorimetric indicator (b), digital image of an interdigitated electrode coated with PANI and used as an electrochemical sensor(c).

References

S.W. Verbruggen, J. Photochem Photobiol. C, Photochem Rev, 24 (2015) 64.
R. Andreozzi, et al., Catal Today, 53 (1999) 51.

Acknowledgement: This work was performed within MoZEES, a Norwegian Centre for Environment-friendly Energy Research (FME), co-sponsored by the Research Council of Norway (project number 257653) and 40 partners from research, industry and public sector. We also acknowledge support from the Research Council of Norway under the CO2BioPEC project 250261.

UM6

From inorganic chemistry to components for Li-/Na-ion batteries - insight from operando studies.

Helmer Fjellvåg

Department of Chemistry / SMN, University of Oslo

Inorganic materials chemistry plays a major role in development of materials for Li- and Na-ion battery technology. Different requirements apply depending on whether the material will enter as the electroactive material in a cathode or an anode, or whether it takes a role as solid state electrolyte. Improved materials are highly requested in order to develop new technology that may provide higher energy capacities in batteries for e.g. the transportation sector. In this talk some principles related to chemical bonding, redox properties and atomic arrangement will be discussed. The effect of nanostructuring of materials will be demonstrated by examples. Information on how an electrode material performs during cycling (charge/discharge) is obtained from electrochemical data, however, we will show the importance of performing operando studies by X-ray methods (home lab and at synchrotrons) for gaining essential insight into mechanisms related to redox, conversion and intercalation reactions, and thereby reversibility and capacity fading.

UM7

High capacity magnesium batteries using solvent-controlled charge storage.

Lu Wang ^a, Zhaohui Wang ^a,b, Per Erik Vullum ^b,c, Sverre Magnus Selbach ^a, Ann Mari Svensson ^a,Fride Vullum-Bruer ^a

^aDepartment of Materials Science and Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim, NORWAY ^b SINTEF Industry, NO-7491 Trondheim, Norway^c Department of Physics, Norwegian University of Science and Technology, 7491 Trondheim, Norway
E-mail: fride.vullum-bruer@ntnu.no

The increased demand for portable as well as stationary energy storage has in the last few decades lead to heavy research efforts into a variety of battery chemistries. Li-ion batteries is still dominating the marked for small-scale electronics as well as electric vehicles. However, as more and more devices are electrified and the demand for tailored batteries increase, new chemistries become significantly more important. One of the more promising new technologies is the Mg-ion battery (MIB) due to higher safety, chemical stability and a high natural abundance in the Earth’s crust (13.9% as compared to 7*10^-4 % for Li). In addition, Mg has a theoretical volumetric capacity of 3833 mAh/cm³, nearly twice that of Li (2061 mAh/cm³), indicating the potential of MIB to reach a high volumetric energy density.^{1, 2} There are however, several issues hampering a fast development of MIBs, including finding suitable electrolytes as well as good cathode materials capable of providing high specific capacity and power density, good rate performance, and long-term stability. And one of the main issues for the cathode materials is poor diffusion of the divalent Mg ion in the host material.

Here, we present a Mg battery using Mn₃O₄ as the electrode material and Mg metal as the counter electrode in a Mg organohaloaluminate electrolyte. The material has been investigated both as cathode and anode, simply by changing the cut-off voltage during electrochemical testing. The reversible capacity when Mn₃O₄ was used as cathode reached ~580 mAh g⁻¹ at a current density of 15.4 mA g⁻¹, whereas a reversible capacity of ~1800 mAh g⁻¹ was obtained in an anode configuration. As a cathode, the Mn₃O₄ showed excellent cycling stability with no loss of capacity after 500 cycles at a current density of 770 mA g⁻¹. As an anode, the stability was not as good and Mn₃O₄ retained 86% of its initial capacity after 200 cycles. By careful investigation using quantitative kinetics analysis in addition to TEM with EDX and EELS it was found that these exceptional charge storage properties and high cycling stability are attributed to highly reversible interfacial reactions involving the electrolyte solvents. Density functional theory calculations were also conducted, which support these findings.

Acknowledgements:
Norwegian Research Council for funding (Grant Number 221785). Computational resources were provided by the Norwegian Metacenter for Computational Science (NOTUR) through the project NN9264K and NTNU243.

References:

M. Matsui, J. Power Sources, 196 (2011), 7048.
C. Ling, D. Banerjee and M. Matsui, Electrochim. Acta, 76 (2012), 270.

UM8

Electrospinning of Ba_0.85Ca_0.15Zr_0.10Ti_0.90O₃ nanofibers for flexible nanogenerators.

Per Martin Rørvik*, Mathieu Grandcolas, Christelle Denonville, and Tor Olav Sunde

SINTEF, Forskningsveien 1, Oslo, Norway
*Corresponding Author: per.martin.rorvik@sintef.no

Certain piezoelectric applications require large-area and flexible devices, for instance for energy harvesting from wearable devices [1] or anti-fouling membranes for water treatment [2]. Electrospinning of nanofibers into a mat is a useful method for fabrication of the active piezoelectric material for such flexible devices. Here, nanofiber mats of the lead-free piezoelectric oxide Ba0.85Ca0.15Zr0.10Ti0.90O3 (BCZT) were made by electrospinning using an Elmarco NS needleless electrospinner, followed by annealing in air. The BCZT mat was put together with electrode polymer films into a flexible flat device and mechanical energy harvesting was demonstrated by recording voltage output when bending the device.

References

Q. Yang, et al., Journal of Alloys and Compounds, 688, 1066-1071 (2016)
J. Bae, et al., Chemical Engineering Journal, 307, 670–678 (2017)

UM9

Verification of hierarchical porosity in CuSAPO-34 by in situ XAS, N₂ adsorption measurements and NO_x removal.

Guro Sørli,Dragos Stoian†, Magnus Rønning§,Karina Mathisen

*Department of Chemistry, §Department of Chemical Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway
†Swiss Norwegian Beam Lines, European Synchrotron Radiation Facility, Grenoble, France
guro.sorli@ntnu.no

Removal of NOx from combustion processes made headlines in 2015 following the so-called “diesel-gate”, showing that new development and research concerning deNOx technology is still highly topical1. Copper containing, microporous SAPO-34 has shown great activity concerning selective reduction of NOx (NH3-SCR and HC-SCR) and may be thought of as a new possible catalyst for NOx removal from internal combustion engines2-6. These catalysts are known to suffer from instability concerning copper addition and deactivation due to coking. The goal of this project is to solve these challenges by introducing mesopores to create so-called hierarchical CuSAPO-34 to relieve the mass transfer issues.

Different structure directing agents have been used to obtain hierarchical CuSAPO-34 and comparisons have been made with the conventional microporous analogue. In-situ XAS data has been recorded at the Swiss-Norwegian Beam Lines (SNBL, BM 31) at the ESRF in Grenoble, France in order to obtain information about the reducibility and size of copper clusters in the samples. Multivariate curve resolution (MCR) analysis has been utilised to obtain reduction profiles of copper. Results from in situ XAS analysis have been correlated with BET surface area and BJH pore size distribution measurements. In the presence of copper, the structure directing agent (SDA)-pair diethylamine (DEA) + tetraethylenepentamine (TEPA) yields a high degree of mesoporosity in CuSAPO-34, whereas the SDA-constellation morpholine (MOR) + TEPA + cetyltrimethylammonium hydroxide (CTAOH) yields mostly micropores. The pore distribution show a large number of mesopores ranging from 30 – 200 Å in the former, correlating with 100 m2/g external/meso area from the t-plot, not present in the sample made with CTAOH. The introduction of mesopores greatly affects the reducibility of copper during temperature programmed reduction (TPR) by H2 (75%), as copper is completely reduced at 490°C in the sample containing mesopores, but 20% CuI-O remains in the microporous sample, even at 700°C. The introduction of mesopores is again reflected in the obtained copper particle sizes from EXAFS analysis, as the mesoporous CuSAPO-34 hosts clusters of 14 Å (NCu-Cu = 8) whereas they are found to be 9 Å (NCu-Cu = 6) in the sample with mainly micropores (the method of corrected multiplicities were employed for the latter sample).

Employing HC-SCR deNOx as a model reaction, the introduction of mesopores greatly improves the NOx conversion over the whole temperature range (275- 500°C), but especially in the low temperature range (<375°C). Whereas the hierarchical CuSAPO-34 made with DEA-TEPA becomes active at 325°C reaching maximum conversion of 67% at 400°C, the microporous
becomes active at 375°C and reaches maximum conversion of 52% at 450°C. Clearly, altering the porosity of CuSAPO-34 has great impact on chemical and catalytic behaviour of the zeotype.

References

R. Hotten, Journal, 2015.
U. Deka, I. Lezcano-Gonzalez, S. J. Warrender, A. Lorena Picone, P. A. Wright, B. M. Weckhuysen and A. M. Beale, Microporous and Mesoporous Materials, 2013, 166, 144-152.
T. Jakobsen, Master Thesis, NTNU, 2014.
K. A. Lomachenko, E. Borfecchia, C. Negri, G. Berlier, C. Lamberti, P. Beato, H. Falsig and S. Bordiga, Journal of the American Chemical Society, 2016, 138, 12025-12028.
M. Moliner, C. Martínez and A. Corma, Chemistry of Materials, 2014, 26, 246-258.
D. Wang, L. Zhang, K. Kamasamudram and W. S. Epling, ACS Catalysis, 2013, 3, 871-881.

UM10

Coupled hydration, cation reorganization and oxidation in MIEC perovskites.

Ragnar Strandbakke*¹, Tor S. Bjørheim¹, Aleksandra Mielewczyk-Gryń², Sebastian Wachowski², Iga Lewandowska², Maria Gazda², María Balaguer³, Jose M. Serra³, Magnus H. Sørby⁴, Truls Norby¹

Department of Chemistry, University of Oslo, FERMiO, Gaustadalléen 21, NO-0349 Oslo, Norway.
Department of Solid State Physics, Faculty of Applied Physics and Mathematics, Gdańsk University of Technology, Narutowicza street s11/12, 80-233 Gdańsk, Poland
Instituto de Tecnología Química (Universitat Politècnica de València - Consejo Superior de Investigaciones Científicas), Avenida de los Naranjos s/n.46022 Valencia, Spain
Department for Neutron Materials Characterization, Institute for Energy Technology, NO-2027 Kjeller, Norway

Tel.: +47-22840660
ragnarst@smn.uio.no

Hydration of some La-containing Co-based perovskites and double perovskites is characterized by an initial fast mass gain followed by a much slower and larger weight increase. The latter process has equilibrium times of typically five days for a pre-calcined powder at 400°C, accounting for around 80% of the total weight gain. Dehydration exhibits the same initial fast weight drop and a following slow weight loss. We hypothesize that the initial hydration changes the lattice so as to induce a slower secondary process. If the secondary process was a second hydration, dehydration would still be fast when water vaour was removed. This is however not the case, hence the secondary process must reflect another reaction. The exchange of oxygen is pronounced in these mixed conducting cobaltites, and we believe that hydration changes the degree of cation order, which in turn alters oxidation thermodynamics.

In double perovskites with the general formula A^IA^IIB₂O_6-δ, oxygen vacancies are formed to compensate for the size mismatch between Ba at A^I and a lanthanide (Ln) at A^II. The result is an increased Co radius, which accounts for most of the size compensation. At 300°C, tetragonal BaLaCo₂O_6-δ(BLC) shows a δ of 0.1,[1] Ba_1-xGd_0.8-yLa_0.2+x+yCo₂O_6-δ with x=y=0 (BGLC1082) shows a δ of 0.35 [2] and BaGdCo₂O_6-δ (BGC) shows a δ of 0.5.[3] BGLC1082, exhibiting an intermediate oxidation of Co with respect to BLC and BGC, is shown to hydrate at high temperatures.[4] While hydration of BGC is limited, hydration of BGLC decreases with increasing x and increases with increasing y, before it returns to near zero at x=0, y=0.8 (BLC).

Regarding the fast and slow mass exchange, we suggest that as hydration affects local structure and, in turn, preferred Co oxidation states, a reorganization of La with respect to Ba or Gd may be induced. As such, local domains of BLC (ordered or disordered) and BGC or local cation disorder may be formed, affecting overall oxidation thermodynamics. The result is that mass exchange in varying pH₂O and constant pO₂ may be misinterpreted as only hydration when it could rather be a mix of hydration and oxidation. DFT calculations are utilized to establish formation energies of protonic defects and oxygen vacancies at favourable hydration sites surrounding Gd/La, thermogravimetry is used to determine hydration – and/or oxidation – upon isothermal switches between wet and dry atmospheres, and activation energies for fast and slow processes are used as indicators of hydration and oxidation induced by cation diffusion.

The research leading to these results has received funding from the Research Council of Norway (Grant nᵒ 272797 “GoPHy MiCO”) through the M-ERA.NET Joint Call 2016.

References

C. Bernuy-Lopez, K. Høydalsvik, M.-A. Einarsrud, T. Grande, Materials 9 (2016) (3) 154.
E. Vøllestad, M. Schrade, J. Segalini, R. Strandbakke, T. Norby, J. Mater. Chem. A 5 (2017) (30) 15743.
D.S. Tsvetkov, I.L. Ivanov, A.Y. Zuev, Solid State Ionics 218 (2012) 13.
R. Strandbakke, et al., Solid State Ionics 278 (2015) 120.

UM11

Interplay between electronic structure calculations and advanced characterisation methods for functional oxides.

Sverre M. Selbach

FACET – Functional Materials and Materials Chemistry Research Group,
Department of Materials Science and Engineering, NTNU – Norwegian University of Science and Technology

Increasing computational resources together with new and rapidly improving characterization techniques expand our possibility to understand structure-property relationships at the microscopic level, which lies at the heart of materials chemistry. In this talk recent efforts to combine DFT calculations with scanning probe microscopy and synchrotron and neutron total scattering in the Functional Materials and Materials Chemistry (FACET) research group at NTNU will be presented. The combined theoretical and experimental approach is illustrated by the following examples: i) structural disorder across an improper ferroelectric phase transition, ii) structural disorder in relaxor piezoelectrics with complex compositions, iii) point defects at ferroelectric domain walls with unusual electronic properties. Finally, the phenomenon of chemical expansion, imperative to multiple fields of solid state chemistry, is revisited, emphasizing the important role of electronic structure.

UM12

Material screening for battery application – DFT study

P. Vajeeston, F. Bianchini, H. Fjellvåg

Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, P.O. Box 1033, N-0315 Oslo, Norway

The demand for novel storage technology for electrochemical energy is rapidly increasing due to the proliferation of renewable energy sources and the emerging markets of grid-scale battery applications. This ongoing research for novel battery technology has been considerably adjuvated by the emergence of computational first-principle modelling techniques, such as Density Functional Theory (DFT), capable of providing accurate insights into the performance of functional materials. In our research, we address two of the main challenges in the field: the development of efficient electrode materials for Li/Na-ion batteries and the research of novel super-ionic conductors for application as solid electrolytes. We provide several examples to illustrate the usage of DFT to assess the stability of certain phases and to model the discharge curve (and thus the cell voltage) of cathode materials, as well as to model the ionic diffusivity of alkaline ions in solid electrolytes. The so evaluated diffusion barrier is employed, together with geometrical considerations regarding the dimensionality of the diffusive framework, to evaluate the suitability of a set of candidates for efficient battery applications.

UM13

Tailoring the domain structure in improper ferroelectrics by defect chemistry.

D. R. Småbråten*, T. S. Holstad, D. Meier, and S. M. Selbach

Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.
*E-mail: didrik.r.smabraten@ntnu.no

Understanding the domain wall (DW) dynamics in ferroelectrics is key to controlling and fine-tune the domain structure, and hence the ferroelectric properties. The DW dynamics strongly couples to the defect chemistry, where point defects may act as possible pinning centers. The overall aim of this study is to give chemical guidelines for how to control the DW mobility in ferroelectrics by controlling the defect chemistry. As a model system, we have chosen the improper ferroelectric hexagonal manganites, because of their complex and exotic domain structure, including features such as stable neutral and charged head-to-head and tail-to-tail DWs, and topologically protected vortex cores. In addition, they possess large chemical flexibility, where donor and acceptor doping of both cation sublattices, as well as both oxygen deficiency and excess, are observed experimentally. This makes the hexagonal manganites an ideal model system for studying the interplay between the defect chemistry and DW mobility in ferroelectrics. From density functional theory (DFT) calculations, we determine the microscopic origin for DW pinning by defects, where the predicted trends are corroborated by piezo force microscopy (PFM) images on doped single crystals.

UM14

Effect of Crystallographic Orientation on the Out-of-Plane and In-Plane Ferroelectric Properties of BaTiO₃Thin Films.

T.M. Ræder,*, E. Khomyakova, J. Glaum, M.A. Einarsrud, T. Grande

Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, Trondheim, Norway
*Corresponding Author: trygve.m.rader@ntnu.no

BaTiO₃ is a widely used ferroelectric material for dielectric applications, and thin films of BaTiO₃ are also of interest for optical modulators, ferroelectric memory, as well as other devices. Parallel plate electrodes (PPEs) have recently been used to explore the dependence of the ferroelectric properties on the crystallographic orientation of BaTiO₃ thin films.[1] However, interdigitated electrodes (IDEs) are also relevant for many applications. For this geometry, the electric field is predominantly in-plane, while for PPEs it is out-of-plane. The two geometries are schematically shown in Figure 1. IDEs have previously been compared to PPEs on PZT films, where it was found that IDE structures show higher coercive fields, saturation polarization, and remnant polarization.[2] Additionally, recent advances in the understanding of IDEs makes it easy to correct for geometric factors and extract the relevant material properties.[3]

Figure 1. Schematic drawing of a) PPE and b) IDE geometry on BaTiO₃thin films.

In this work, epitaxial BaTiO₃ films are made using aqueous chemical solution deposition on monocrystalline SrTiO₃ (STO) substrates. (001), (011), and (111) oriented STO substrates are used in combination with both PPE and IDE geometries. Due to a mismatch in thermal expansion coefficient and the high thermal annealing temperature of the films, in-plane biaxial tensile strain is developed during cooling of the films, favoring the development of a-domains. This affects the ferroelectric properties in films with both PPEs and IDEs, but the effect is different for the two geometries. Moreover, IDEs are deposited at several angles relative to the substrate orientation, so that the properties are measured along different in-plane crystallographic directions. The BaTiO₃ films are characterized by a combination of X-ray diffraction, transmission electron microscopy, dielectric spectroscopy and ferroelectric characterization.

References

T. Hosokura, A. Ando, T. Konoike. RSC Advances 5.118 (2015): 97563-97567.
N. Chidambaram, et al. IEEE transactions on ultrasonics, ferroelectrics, and frequency control 60.8, 1564-1571 (2013)
R. Nigon, T.M. Raeder, P. Muralt, Journal of Applied Physics 121.20, 204101 (2017)

UM15

Theoretical approach to understand the origin of BZY grain boundary resistance.

Tarjei Bondevik^a, Ole Martin Løvvik^a,b, Truls Norby^a

^aCentre for Materials Science and Nanotechnology, University of Oslo, Norway^bSINTEF Materials Physics, Oslo, Norway
*tarjei.bondevik@smn.uio.no

Y-substituted BaZrO₃ (BZY) exhibits high grain interior proton conductivity1, but grain boundaries (GBs) have large resistances, commonly attributed to charge carrier depletion in space charge layers next to positively charged GB cores2,3. The chemical environment at the GB is substantially different than in bulk. Even in materials such as BZY, where normally no secondary phases are observed at the GB, a structural perturbation over several atomic planes typically occurs next to the GB core. The structural perturbation affects the electrical conductivity in two ways. First, charged defects segregate towards the GB core, leading to a depletion of charge carriers in space charge layers next to the core, hence reducing the conductivity. Second, the electrical mobility around the GB core may also differ compared to bulk, possibly reducing the conductivity further.

In this work, we investigate the GBs with a theoretical approach to find the origin of the reduced electrical conductivity. A natural choice of method is density functional theory (DFT) calculations. However, such calculations can only be performed on a very limited number of GBs. As the GBs get more complex, the number of atoms needed to describe them in a periodic supercell increases. With the computational cost going roughly as the number of atoms cubed, only the simplest GBs can be described with DFT.

To reduce the computational cost with up to 90 percent, we combine DFT with machine learning algorithms. Further, we also apply classical interatomic potential, which has a computational cost several orders of magnitude lower than DFT. By combining these approaches, we can investigate numerous BZY grain boundaries. Specifically, we calculate the segregation energies and electrical mobility around the GB core, and relate these quantities to experimentally measured GB resistance. The ultimate goal is to gain a fundamental understanding of the origin of the grain boundary resistance, and test the space charge model.

Acknowledgement: This work is part of the nationally coordinated project Functional OXides for Clean Energy Technologies (FOXCET, RCN, 228355), with SINTEF, NTNU and UiO as active partners.

References

E. Fabbri, D. Pergolesi, and E. Traversa, “Materials challenges toward proton-conducting oxide fuel cells: a critical review,” Chemical Society Reviews, vol. 39, pp. 4355–4369, 2010.
X. Guo and R. Wasser, “Electrical properties of the grain boundaries of oxygen ion conductors: Acceptor-doped zirconia and ceria,” Progress in Materials Science, vol. 51, pp. 151–210, 2006.
J. Nowotny, The CRC Handbook of Solid State Electrochemistry, CRC Press, 1997.

UM16

Cation disordering in tetragonal tungsten bronzes.

S. S. Aamlid,* S. M. Selbach, and T. Grande

Department of Materials Science and Engineering, NTNU Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
*Corresponding Author: solveig.s.aamlid@ntnu.no

Tetragonal tungsten bronzes (TTB) have the general formula A2₄Al₂C₄B₁₀O₃₀. The A1 and A2 cation sites are of similar size, as shown in Figure 1, and may accommodate similar types of cations such as alkali and alkaline earth elements. The solid solution Sr_5xBa_5-x⎕Nb₁₀O₃₀ (SBN, 0.25<x<0.75) is a common example of a ferroelectric tungsten bronze. SBN is unfilled, meaning that one of the A sites are vacant and the remaining five are occupied by a mixture of Ba and Sr. Ba prefers the A2 site while Sr weakly prefers the A1 site. The effect of thermal history on the Curie temperature has been reported in SBN in early works [1]. Quenching from high temperatures is inferred to induce cation disorder and an increase in Curie temperature for SBN. First principles DFT simulations of the end members in SBN have demonstrated that several cation configurations are similar in energy, and that the degree of disorder will depend on both thermal history and on the Sr/Ba ratio [2].

Figure 1. The tetragonal tungsten bronze structure, showing the large pentagonal A2 sites and the smaller square A1 sites.

Here, the effect of cation disorder in SBN tungsten bronzes is further investigated. Dense pellets of SBN in four compositions were prepared by solid state synthesis and quenched from high temperatures to freeze in various degrees of cation disorder. The effect of thermal history was characterized experimentally by dielectric spectroscopy, ferroelectric hysteresis measurements, and X-ray diffraction. The disordering at high quenching temperatures caused an increase in Curie temperature, ferroelectric hardening, a contraction of the unit cell in the a parameter, and the vacancy distribution shifting from the A2 to the A1 site [3].

References

R. Guo et al., Ferroelectrics, 93, 397-405 (1989).
G. H. Olsen, S. M. Selbach, T. Grande. Phys Chem Chem Phys, 17, 30343-30351 (2015)
S. S. Aamlid, S. M. Selbach, T. Grande, to be submitted

UM17

The chemistries of proton ceramic electrochemical cells,

Truls Norby

Dept. Chemistry, Univ. Oslo, SMN, FERMiO, Gaustadalléen 21, NO-0349 Oslo, Norway

Proton ceramic electrochemical cells comprise proton conducting ceramic electrolytes and various metallic or oxidic electrodes depending on conditions and processes. Their development from discovery towards commercialisation is relatively recent and faces many challenges. However, the use of optimised materials and their combinations for various uses such as fuel cells, steam electrolysers, and natural gas processing has led to remarkable progress and attention [1-4]. In Norway this comprises fundamental and applied studies at UiO and NTNU in collaboration with SINTEF Industry as well as materials synthesis by CerPoTech AS and developments in fabrication and applications by CoorsTek Membrane Sciences AS (CTMS).

In this contribution, we will review the chemistries at play in state-of-the art electrolytes (BaZrO₃-based perovskites), reducing side electrodes (negatrodes, typically Ni-based cermets), and oxidising side electrodes (positrodes, typically barium and transition metal-based double perovskites). This comprises the thermodynamic and kinetic stability of individual phases and their interfaces during fabrication and operation as well as the kinetics of solid-state transport and heterogeneous gas-solid reactions at surfaces and interfaces including electrodes. Some recent developments in advancement of electrocatalytic activity of the electrodes will be highlighted, covering promotion of mixed proton electron conduction and in situ exsolution of nanostructures and catalytic nanoparticles.

References

C. Duan et al. «Readily processed protonic ceramic fuel cells with high performance at low temperatures», Science, 349 (2015) 1321.
S. Choi et al. Exceptional power density and stability at intermediate temperatures in protonic ceramic fuel cells. Nature Energy, 3 (2018) 202.
S.H. Morejudo et al., "Direct conversion of methane to aromatics in a catalytic co-ionic membrane reactor", Science, 353 [6299] (2016) 563.
H. Malerød-Fjeld et al., “Thermo-electrochemical production of compressed hydrogen from methane with near-zero energy loss”, Nature Energy, 2 [12] (2017) 923.

Acknowledgement: Much of the work to be reviewed has to a large extent been performed by colleagues at Norwegian partner institutions SINTEF, NTNU, and CTMS in numerous RCN-funded projects especially in the ENERGIX and NANO2021 programmes (e.g. “FOXCET”), as well as with international partners in the EU Energy and FCH JU projects “EFFIPRO”, “ELECTRA”, and “GAMER” and the EU ERA and MERA NET projects “Proton” and “GoPhyMiCo”.

Det 21. Landsmøte i kjemi

Foredrag - Abstracts

FE - Fellesarrangement

GW

Guldberg-Waage-foredrag

Hydrogen

Truls Norby

Kjemisk Institutt, Universitetet i Oslo

FE1

Bottom-up Assembly of Active, Autonomous and Complex Bioinspired Systems with Adaptive Behaviour

Daniela Wilson

Systems Chemistry, Radboud University Nijmegen, Institute for Molecules and Materials Nijmegen, The Netherlands d.wilson@science.ru.nl

FE2

Molecular Assemblers, Molecular Machines Performing Synthesis

R. Herges

Otto-Diels Institute for Organic Chemistry, University of Kiel, Germany

FE3

Industry lecture

Radionuclides and cancer treatment: How to succeed

Roy Larsen

Oncoinvent AS

FE4

Integrating cryogenic ion chemistry and spectroscopy: Capture and characterization of reaction intermediates in homogeneous catalysis

Mark Johnson

Yale Univerisity

FE5

Semi-artificial Photosynthesis

Erwin Reisner

Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK E-mail: reisner@ch.cam.ac.uk Web: http://www-reisner.ch.cam.ac.uk/

AN - Analytisk kjemi

AN1

ISO/IEC 17025:2017 - en oppdatert versjon av verdens mest brukte akkrediteringsstandard som omfatter generelle krav til prøvings- og kalibreringslaboratoriers kompetanse

Oversikt over endringer og likheter sammenlignet med ISO/IEC 17025:2005.

Maarten Aerts

Norsk Akkreditering

AN2

Validering av metode - Hvorfor, hvordan og når er det nødvendig?

Elin Lovise Folven Gjengedal

Norges miljø- og biovitenskapelige universitet, Fakultet for miljøvitenskap og naturforvaltning, Ås

AN3

Utfordringer ved bestemmelse av deteksjonsgrenser

Grethe Wibetoe

Kjemisk institutt, Universitetet i Oslo

AN4

Analytical challenges in Forensic Toxicology

Veronica Horpestad Liane

Division of Laboratory Medicine, Department of Forensic Sciences, Oslo University Hospital

AN5

Kjemiske våpen – jakten på bevis.

Bent-Tore Røen

Forsvarets Forskningsinstitutt

AN6

Pollutants in the Arctic.

Roland Kallenborn1, Simon Wilson2, Lars-Otto Reiersen3

1. Norwegian University of Life Sciences (NMBU), Ås & University Centre in Svalbard (UNIS), Longyearbyen; 2. Arctic Monitoring and Assessment Programme (AMAP), Tromsø; 3. Arctic Knowledge, Tromsø

AN7

Organ on a chip: analysis of mini-organs for personalized medicine.

Frøydis Sved Skottvoll

Department of Chemistry, University of Oslo

AN8

Metabolomics with mass spectrometry: a powerful tool for clinical analyses.

Skogvold HB1, Sandås EM1, Østeby A1, Rootwelt H1, Arnesen CE1, Wilson SRH2, Rønning PO3, Elgstøen KBP1

1. Oslo University Hospital, Oslo, Norway 2. University of Oslo 3. Oslo Metropolitan University

AN9

Sporelementer i sjømat og andre marine prøver -Status og utvikling innen analysemetoder.

Veronika Sele

Havforskningsinstituttet

AN10

Measuring with an MC-ICPMS, examples in earth sciences

Cedric Hamelin

Department of Earth Science, UiB

AN11

Den norske NMR-plattformen – En plattform for dine kjemiske analyser

Jarl Underhaug

Universitetet i Bergen

AN12

Bruk av kjemometriske metoder i analytisk kjemi.

Knut Dyrstad

KD Metrix

KA - Katalyse

Systems Chemistry, Radboud University Nijmegen, Institute for Molecules and Materials Nijmegen, The Netherlands
d.wilson@science.ru.nl

Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
E-mail: reisner@ch.cam.ac.uk
Web: http://www-reisner.ch.cam.ac.uk/

Roland Kallenborn¹, Simon Wilson², Lars-Otto Reiersen³

1. Norwegian University of Life Sciences (NMBU), Ås & University Centre in Svalbard (UNIS), Longyearbyen;
2. Arctic Monitoring and Assessment Programme (AMAP), Tromsø;
3. Arctic Knowledge, Tromsø

Skogvold HB¹, Sandås EM¹, Østeby A1, Rootwelt H¹, Arnesen CE¹, Wilson SRH², Rønning PO³, Elgstøen KBP¹

1. Oslo University Hospital, Oslo, Norway
2. University of Oslo
3. Oslo Metropolitan University

Faculty of Science and Engineering, Materials Chemistry — Zernike Institute for Advanced Materials, University of Groningen, The Netherlands
moniek.tromp@rug.nl

Univ. Lyon, Univ. Claude Bernard Lyon 1, CNRS, IRCELYON - UMR 5256, Villeurbanne, France.
jerome.canivet@ircelyon.univ-lyon1.fr

Department of Chemical Engineering, NTNU, Trondheim
*ole.h.bjorkedal@ntnu.no

E. Borfecchia¹*, D. K. Pappas¹, M. Dyballa¹, A. Martini^2,3, K. A. Lomachenko⁴, G. Berlier², P. Beato⁵, C. Lamberti^3,6, S. Bordiga^1,2, U. Olsbye¹, S. Svelle¹

Christian Ahoba-Sam^1,2*, Unni Olsbye¹ and Klaus-Joachim Jens²

Department of Energy and Petroleum Engineering, University of Stavanger, 4036 Stavanger, Norway
* corresponding zhixin.yu@uis.no

Kristian Stangeland¹, Dori Yosef Kalai, Zhixin Yu*²

1 – Department of Energy and Petroleum Engineering, University of Stavanger, 4036 Stavanger, Norway
* corresponding Zhixin.yu@uis.no

Hilde J. Venvik¹*, Marie Døvre Strømsheim¹, Ingeborg-Helene Svenum², Mari Helene Farstad¹, Kees-Jan (C.J.) Weststrate³, Anne Borg⁴

CO₂ Hydrogenation over Functionalized UiO Zr-MOFs

A. Lazzarini¹,*, G. Kaur¹, E. S. Gutterød¹, S. Øien Ødegaard¹, K. P. Lillerud¹, U. Olsbye¹, and S. Bordiga^1,2

Facile synthesis approach for core-shell TiO₂–CdS nanoparticles for enhanced photocatalytic H₂ generation from water

Muhammad Zubair¹, Ingeborg-Helene Svenum^1,2, Magnus Rønning¹, Jia Yang¹*

1 – Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), Sem Sælands vei 4, NO-7491, Trondheim, Norway
2 – SINTEF Industry, P. O. Box 4760 Torgarden, N-7465, Trondheim, Norway

Gurpreet Kaur,¹ Sigurd Øien-Ødegaard,¹ Knut Tormodssønn Hylland¹, Andrea Lazzarini¹, Sachin Maruti Chavan¹, Silvia Bordiga^1,
2, Mats Tilset¹, Unni Olsbye¹ and Karl Petter Lillerud¹*