The main topic of the research group is concerned with novel fundamental experimental investigations of weakly bound cluster molecules by complementary THz cluster spectroscopy approaches, which are complemented by first principles quantum chemical modeling. An ultimate challenge for the physical sciences is to describe accurately how the properties of macroscopic phenomena known from the energy, material and life sciences emerge from the interplay between non-covalent forces as directional hydrogen bonding, non-directional and long-range London dispersion forces and short-range steric repulsion between molecules.

Examples from the experimental part of the program are THz studies of weakly bound cluster molecules embedded in soft “quantum crystals” of 99.9% enriched para-hydrogen or isolated in high-throughput pulsed supersonic jet expansions (collaboration partner) and high-resolution THz synchrotron gas phase studies of prototypical systems at the large-scale synchrotron facilities SOLEIL Synchrotron and Canadian Light Source, Inc. The detailed spectroscopic characterization and quantum chemical modeling of molecular recognition phenomena and the complex hydrogen bond networks involved in micro-solvation of organic molecules have been a key interest in recent years.

In addition, several internal collaborations at DTU Chemistry concerned with spectroscopic characterization of novel metal-organic frameworks (molecular materials), organo-metallic complexes (green chemistry), polymers (functional materials) and enzymes (bio-catalysis) have recently been established. Another recent novel complementary activity is concerned with resonance-enhanced nano-IR surface spectroscopy at high spatial resolution (10 nm) beyond the diffraction limit for chemical mapping of material surfaces.

Selected Peer-Reviewed Journal Publications

[70] R. Padilla, Z. Ni, D. Mihrin, R. Wugt Larsen and M. Nielsen, "Catalytic Base-Free Transfer Hydrogenation of Biomass Derived Furanic Aldehydes with Bioalcohols and PNP Pincer Complexes", ChemCatChem 15, e202200819 (2023). Front Cover Read/Download [Open Access, CC BY-NC-ND 4.0]

[68] D. Mihrin, A. Voute, P. W. Jakobsen, K. L. Feilberg and R. Wugt Larsen, "The Effect of Alkylation on the Micro-Solvation of Ethers Revealed by Highly Localized Water Librational Motion ", Journal of Chemical Physics 156, 084305 (2022). Read/Download

[67] H. Chen, L. Voigt, M. Kubus, D. Mihrin, S. Mossin, R. Wugt Larsen, S. Kegnæs, S. Piligkos and K. S. Pedersen, "Magnetic Archimedean Tessellations in Metal-Organic Frameworks", Journal of the American Chemical Society 143, 14041-14045 (2021). Inside Front Cover Read/Download

[66] L. Voigt, R. Wugt Larsen, M. Kubus and K. S. Pedersen, "Zero-Valent Metals in Metal-Organic Frameworks: fac-M(CO)₃(pyrazine)_3/2", Chemical Communications 57, 3861-3864 (2021).  Inside Front Cover Read/Download

[61] M. G. Vinum, L. Voigt, S. H. Hansen, C. Bell, K. M. Clark, R. Wugt Larsen and K. S. Pedersen, "Ligand Field-Actuated Redox-Activity of Acetylacetonate", Chemical Science 11, 8267-8272 (2020). Read/Download [Open Access, CC BY 3.0]

[59] J. Andersen, R. Wugt Larsen, J. Ceponkus, P. Uvdal and B. Nelander, "Far-Infrared Investigation of the Benzene-Water Complex: The Identification of Large-Amplitude Motion and Tunneling Pathways", Journal of Physical Chemistry A 124, 513-519 (2020). Read/Download

[56] D. Mihrin, P. W. Jakobsen, A. Voute, L. Manceron and R. Wugt Larsen, "High-Resolution Infrared Synchrotron Investigation of (HCN)₂ and a Semi-Experimental Determination of the Dissociation Energy". ChemPhysChem 20, 3238-3244 (2019). Selected for "2019 Edition of SOLEIL Highlights" Read/Download  [Open Access, CC BY 3.0]

[53] D. Mihrin, J. Andersen, P. W. Jakobsen and R. Wugt Larsen, "Highly Localized H₂O Librational Motion as a Sensitive Far-Infrared Spectroscopic Probe for Microsolvation of Organic Molecules". Physical Chemistry Chemical Physics 21, 1717-1723 (2019). Read/Download

[52] D. Mihrin and R. Wugt Larsen, "THz Spectroscopy of Weakly Bound Cluster Molecules in Solid Para-Hydrogen: A Sensitive Probe of van der Waals Interactions". Physical Chemistry Chemical Physics 21, 349-358 (2019). Read/Download

[51] D. Mihrin, P. W. Jakobsen, A. Voute, L. Manceron and R. Wugt Larsen, "High-Resolution Synchrotron Terahertz Investigation of the Large-Amplitude Hydrogen Bond Librational Band of (HCN)₂". Physical Chemistry Chemical Physics 20, 8241-8246 (2018). 2018 PCCP HOT Article Read/Download

[50] J. Andersen, A. Voute, D. Mihrin, J. Heimdal, R. W. Berg, M. Torsson and R. Wugt Larsen, "Probing the Global Potential Energy Minimum of (CH₂O)₂ : THz Absorption Spectrum of (CH₂O)₂ in Solid Neon and Para-Hydrogen". Journal of Chemical Physics 146, 244311 (2017). Read/Download

[49] J. Andersen, J. Heimdal, B. Nelander and R. Wugt Larsen, "Competition between Weak OH··π and CH··O Hydrogen Bonds: THz Spectroscopy of the C₂H₂–H₂O and C₂H₄–H₂O Complexes". Journal of Chemical Physics 146, 194302 (2017). Read/Download

[47] M. Heger, J. Andersen, M. A. Suhm and R. Wugt Larsen, "The Donor OH Stretching-Libration Dynamics of Hydrogen-Bonded Methanol Dimers in Cryogenic Matrices". Physical Chemistry Chemical Physics 18, 3739 (2016). Read/Download [Open Access, CC BY 3.0]

[46] J. Andersen, J. Heimdal and R. Wugt Larsen, "Spectroscopic Identification of Ethanol-Water Conformers By Large-Amplitude Hydrogen Bond Librational Modes". Journal of Chemical Physics 143, 224315 (2015). Read/Download

[45] J. Andersen, J. Heimdal and R. Wugt Larsen, "The Influence of Large-Amplitude Librational Motion on the Hydrogen Bond Energy of Alcohol-Water Complexes". Physical Chemistry Chemical Physics  17, 23761 (2015). Read/Download [Open Access, CC BY 3.0]

[44] F. Kollipost, J. Andersen, D. W. Mahler, J. Heimdal, M. Heger, M. A. Suhm and R. Wugt Larsen, "The Effect of Hydrogen Bonding on Torsional Dynamics: A Combined Far-Infrared Jet and Matrix Isolation Study of Methanol Dimer". Journal of Chemical Physics 141, 174314 (2014). Read/Download

[43] J. Andersen, J. Heimdal, D. W. Mahler, B. Nelander and R. Wugt Larsen, "THz Absorption Spectrum of the CO₂–H₂O Complex: Observation and Assignment of Intermolecular van der Waals Vibrations". Journal of Chemical Physics 140, 091103 (2014). Read/Download

[40] F. Kollipost, R. Wugt Larsen, A. V. Domanskaya, M. Nörenberg and M. A. Suhm, "The Highest Frequency Hydrogen Bond Vibration and an Experimental Value for the Dissociation Energy of Formic Acid Dimer". Journal of Chemical Physics 136, 151101 (2012). Read/Download

[37] M. Nedic, T. N. Wassermann, R. Wugt Larsen and M. A. Suhm, "A Combined Raman and Infrared Jet Study of Mixed Methanol-Water and Ethanol-Water Clusters". Physical Chemistry Chemical Physics 13, 14050 (2011). Themed Issue: Weak Hydrogen Bonds – Strong Effects. Read/Download