ORCID Profile
0000-0001-5533-1163
Current Organisations
University of Göttingen
,
Deutsches Elektronen-Synchrotron
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Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/C9CP06775B
Abstract: The puzzling fine structure in the rotational spectrum of succinic anhydride is explained and a semiexperimental geometry calculated.
Publisher: AIP Publishing
Date: 30-04-2020
DOI: 10.1063/5.0004465
Abstract: The site-specific first microsolvation step of furan and some of its derivatives with methanol is explored to benchmark the ability of quantum-chemical methods to describe the structure, energetics, and vibrational spectrum at low temperature. Infrared and microwave spectra in supersonic jet expansions are used to quantify the docking preference and some relevant quantum states of the model complexes. Microwave spectroscopy strictly rules out in-plane docking of methanol as opposed to the top coordination of the aromatic ring. Contrasting comparison strategies, which emphasize either the experimental or the theoretical input, are explored. Within the harmonic approximation, only a few composite computational approaches are able to achieve a satisfactory performance. Deuteration experiments suggest that the harmonic treatment itself is largely justified for the zero-point energy, likely and by design due to the systematic cancellation of important anharmonic contributions between the docking variants. Therefore, discrepancies between experiment and theory for the isomer abundance are tentatively assigned to electronic structure deficiencies, but uncertainties remain on the nuclear dynamics side. Attempts to include anharmonic contributions indicate that for systems of this size, a uniform treatment of anharmonicity with systematically improved performance is not yet in sight.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0CP00334D
Abstract: Spectroscopy meets theory in a study of Xe⋯OCS complex: accurate near-equilibrium structures, experimental interaction energies, and CCSD(T)/CBS results presented.
Publisher: American Chemical Society (ACS)
Date: 10-01-2020
DOI: 10.26434/CHEMRXIV.11555580.V1
Abstract: The Xe···OCS complex is studied using microwave spectroscopy. Nine isotopologues are measured, and a mass-dependent rm(2) structure is presented. The experiments are supported with a wide array of calculations, including CCSD(T), SAPT, as well as double-hybrid DFT. Trends in the structures of six Rg···OCS complexes (He, Ne, Ar, Kr, Xe, and Hg) are investigated, with particular attention to the deformation of the OCS monomer and relativistic effects. The experimental near-equilibrium structure of Xe···OCS can be predicted to within 11 milliangstrom in the Xe···C distance by correlated wavefunction theory.
Publisher: American Chemical Society (ACS)
Date: 19-01-2018
Abstract: Accurate data sets including noncovalent interactions have become essential for benchmarking computational methods. However, while there is much focus on obtaining an accurate description of relative energies, reliable prediction of accurate equilibrium geometries is also important. To facilitate the benchmarking of computed geometries, the current work includes an accurate data set of semiexperimental equilibrium geometries of noncovalent complexes that can be directly compared to ab initio data. The structures are based on high-accuracy spectroscopic data, combined with vibrational corrections at the double-hybrid density functional level. The current work is designed to complement available data sets of semiexperimental geometries of small rigid molecules and ab initio geometries of complexes. The benchmark-quality data comprises 16 complexes and includes dispersion interactions, hydrogen bonding, CH/π···π interactions, and trimers. In addition to the reference data, accurate counterpoise-corrected geometries have been obtained up to the CCSD level, along with interaction energies. A short overview of the performance of computational methods, including dispersion-corrected B3LYP and B2PLYP functionals, is also included.
Publisher: AIP Publishing
Date: 21-05-2018
DOI: 10.1063/1.5027487
Abstract: The microwave spectra of 10 teflic acid isotopologues were recorded in the frequency range of 3-25 GHz using supersonic jet-expansion Fourier transform microwave spectroscopy. Despite being asymmetric in its equilibrium structure, the delocalization of the hydrogen atom leads to a symmetric top vibrational ground state structure. In this work, we present the zero point structure obtained from the experimental rotational constants and an approach to determine the semi-experimental equilibrium structure aided by
Location: No location found
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