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Bödecker M, Mihrin D, Suhm MA, Wugt Larsen R. Regularities and Anomalies in Neon Matrix Shifts of Hydrogen-Bonded O-H Stretching Fundamentals. J Phys Chem A 2024; 128:7124-7136. [PMID: 39155731 PMCID: PMC11372756 DOI: 10.1021/acs.jpca.4c03468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2024]
Abstract
O-H bond stretching vibrations in hydrogen-bonded complexes embedded into cryogenic neon matrices are subtly downshifted from cold gas phase reference wavenumbers. To the extent that this shift is systematic, it enables neon matrices as more universally applicable spectroscopic benchmark environments for quantum chemical predictions. Outliers are indicative of either an assignment problem in one of the two cryogenic experiments or they reveal interesting dynamics or structural effects on the complexes as a function of the environment. We compile 6 literature-known pairs of experimental data in jet and neon matrix expansions and realize a 6-fold expansion of that number through targeted matrix isolation and/or slit jet expansion spectroscopy presented in this work. In many cases, the neon matrix shift is less than the uncertainty of the currently best-performing blind quantum chemical predictions for the gas phase, but in specific cases, it may exceed the currently achievable theoretical accuracy. Some evidence for a positive correlation of the matrix shift with the hydrogen bond shift is found, similar to observations for helium nanodroplets. Outliers in particular for water acting as a donor are discussed, and in a few cases they call for a future reinvestigation. Substantial improvement in the correlation of the matrix shift with the hydrogen bond shift is achieved for ketone monohydrates by removing a vibrational resonance. New insights into nitrile hydration isomerism are obtained, and the linear OH stretching spectrum of the jet-cooled ammonia-water complex is presented for the first time. Vibrational spectroscopy in weakly perturbing solid rare gas quantum matrices for the benchmarking of gas phase theory and future explicit theoretical treatments of the quantum matrix environment to better understand the outliers are both encouraged.
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Affiliation(s)
- Margarethe Bödecker
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
| | - Dmytro Mihrin
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kgs. Lyngby, Denmark
| | - Martin A Suhm
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
| | - René Wugt Larsen
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, 2800 Kgs. Lyngby, Denmark
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2
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Mata RA, Zhanabekova T, Obenchain DA, Suhm MA. Dispersion Control over Molecule Cohesion: Exploiting and Dissecting the Tipping Power of Aromatic Rings. Acc Chem Res 2024; 57:1077-1086. [PMID: 38537179 PMCID: PMC11025128 DOI: 10.1021/acs.accounts.3c00664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 04/17/2024]
Abstract
ConspectusWe have learned over the past years how London dispersion forces can be effectively used to influence or even qualitatively tip the structure of aggregates and the conformation of single molecules. This happens despite the fact that single dispersion contacts are much weaker than competing polar forces. It is a classical case of strength by numbers, with the importance of London dispersion forces scaling with the system size. Knowledge about the tipping points, however difficult to attain, is necessary for a rational design of intermolecular forces. One requires a careful assessment of the competing interactions, either by sensitive spectroscopic techniques for the study of the isolated molecules and aggregates or by theoretical approaches. Of particular interest are the systems close to the tipping point, when dispersion interactions barely outweigh or approach the strength of the other interactions. Such subtle cases are important milestones for a scale-up to realistic multi-interaction situations encountered in the fields of life and materials science. In searching for examples that provide ideal competing interactions in complexes and small clusters, aromatic systems can offer a diverse set of molecules with a variation of dispersion and electrostatic forces that control the dominant and peripheral interactions. Our combined spectroscopic and theoretical investigations provide valuable insights into the balance of intermolecular forces because they typically allow us to switch the aromatic substituent on and off. High-resolution rotational spectroscopy serves as a benchmark for molecular structures, as correct calculations should be based on correct geometries. When discussing the competition with other noncovalent interactions, obvious competitors are directional hydrogen bonds. As a second counterweight to aryl interactions, we will discuss aurophilic/metallophilic interactions, which also have a strong stabilization with a small number of atoms involved. Vibrational spectroscopy is most sensitive to interactions of light atoms, and the competition of OH hydrogen bonds with dispersion forces in a molecular aggregate can be judged well by the OH stretching frequency. Experiments in the gas phase are ideal for gauging the accuracy of quantum chemical predictions free of solvent forces. A tight collaboration utilizing these three methods allows experiment vs experiment vs theory benchmarking of the overall influence of dispersion in molecular structures and energetics.
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Affiliation(s)
- Ricardo A. Mata
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
| | - Tlektes Zhanabekova
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
| | - Daniel A. Obenchain
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
| | - Martin A. Suhm
- Institute of Physical Chemistry, University of Göttingen, Tammannstrasse 6, 37077 Göttingen, Germany
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3
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Fischer TL, Bödecker M, Schweer SM, Dupont J, Lepère V, Zehnacker-Rentien A, Suhm MA, Schröder B, Henkes T, Andrada DM, Balabin RM, Singh HK, Bhattacharyya HP, Sarma M, Käser S, Töpfer K, Vazquez-Salazar LI, Boittier ED, Meuwly M, Mandelli G, Lanzi C, Conte R, Ceotto M, Dietrich F, Cisternas V, Gnanasekaran R, Hippler M, Jarraya M, Hochlaf M, Viswanathan N, Nevolianis T, Rath G, Kopp WA, Leonhard K, Mata RA. The first HyDRA challenge for computational vibrational spectroscopy. Phys Chem Chem Phys 2023; 25:22089-22102. [PMID: 37610422 DOI: 10.1039/d3cp01216f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Vibrational spectroscopy in supersonic jet expansions is a powerful tool to assess molecular aggregates in close to ideal conditions for the benchmarking of quantum chemical approaches. The low temperatures achieved as well as the absence of environment effects allow for a direct comparison between computed and experimental spectra. This provides potential benchmarking data which can be revisited to hone different computational techniques, and it allows for the critical analysis of procedures under the setting of a blind challenge. In the latter case, the final result is unknown to modellers, providing an unbiased testing opportunity for quantum chemical models. In this work, we present the spectroscopic and computational results for the first HyDRA blind challenge. The latter deals with the prediction of water donor stretching vibrations in monohydrates of organic molecules. This edition features a test set of 10 systems. Experimental water donor OH vibrational wavenumbers for the vacuum-isolated monohydrates of formaldehyde, tetrahydrofuran, pyridine, tetrahydrothiophene, trifluoroethanol, methyl lactate, dimethylimidazolidinone, cyclooctanone, trifluoroacetophenone and 1-phenylcyclohexane-cis-1,2-diol are provided. The results of the challenge show promising predictive properties in both purely quantum mechanical approaches as well as regression and other machine learning strategies.
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Affiliation(s)
- Taija L Fischer
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
| | - Margarethe Bödecker
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
| | - Sophie M Schweer
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
| | - Jennifer Dupont
- Institut des Sciences Moléculaires dOrsay, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Valéria Lepère
- Institut des Sciences Moléculaires dOrsay, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Anne Zehnacker-Rentien
- Institut des Sciences Moléculaires dOrsay, Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Martin A Suhm
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
| | - Benjamin Schröder
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
| | - Tobias Henkes
- Department of Physics and Materials Science, University of Luxembourg, L-1511 Luxembourg City, Luxembourg
| | - Diego M Andrada
- Institute for Inorganic Chemistry, Saarland University, 66123 Saarbrücken, Germany
| | - Roman M Balabin
- Bond Street Holdings, Long Point Road, KN-1002 Henville Building 9, Charlestown, KN10 Nevis, St. Kitts and Nevis
| | - Haobam Kisan Singh
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam-781039, India
| | | | - Manabendra Sarma
- Department of Chemistry, Indian Institute of Technology Guwahati, Assam-781039, India
| | - Silvan Käser
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Kai Töpfer
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Luis I Vazquez-Salazar
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Eric D Boittier
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Giacomo Mandelli
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Cecilia Lanzi
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Riccardo Conte
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, via C. Golgi 19, 20133 Milano, Italy
| | - Fabian Dietrich
- Department of Physics Science, Universidad de La Frontera, Francisco Salazar 01145, Temuco, Chile
| | - Vicente Cisternas
- Department of Physics Science, Universidad de La Frontera, Francisco Salazar 01145, Temuco, Chile
| | - Ramachandran Gnanasekaran
- Vellore Institute of Technology, School of Advanced Sciences (SAS), ChemistryDivision, Chennai 600 027, India
| | - Michael Hippler
- Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK
| | - Mahmoud Jarraya
- U. Gustave Eiffel, COSYS/IMSE, 5 BD Descartes 77454, Champs-sur-Marne, France
| | - Majdi Hochlaf
- U. Gustave Eiffel, COSYS/IMSE, 5 BD Descartes 77454, Champs-sur-Marne, France
| | - Narasimhan Viswanathan
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, D-52072 Aachen, Germany
| | - Thomas Nevolianis
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, D-52072 Aachen, Germany
| | - Gabriel Rath
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, D-52072 Aachen, Germany
| | - Wassja A Kopp
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, D-52072 Aachen, Germany
| | - Kai Leonhard
- Institute of Technical Thermodynamics, RWTH Aachen University, Schinkelstraße 8, D-52072 Aachen, Germany
| | - Ricardo A Mata
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstraße 6, Göttingen, Germany.
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Wu X, Zhou X, Bjelić S, Hemberger P, Sztáray B, Bodi A. A plethora of isomerization processes and hydrogen scrambling in the fragmentation of the methanol dimer cation: a PEPICO study. Phys Chem Chem Phys 2022; 24:1437-1446. [PMID: 34984425 DOI: 10.1039/d1cp05155e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The valence photoionization of light and deuterated methanol dimers was studied by imaging photoelectron photoion coincidence spectroscopy in the 10.00-10.35 eV photon energy range. Methanol clusters were generated in a rich methanol beam in nitrogen after expansion into vacuum. They generally photoionize dissociatively to protonated methanol cluster cations, (CH3OH)nH+. However, the stable dimer parent ion (CH3OH)2+ is readily detected below the dissociation threshold to yield the dominant CH3OH2+ fragment ion. In addition to protonated methanol, we could also detect the water- and methyl-loss fragment ions of the methanol dimer cation for the first time. These newly revealed fragmentation channels are slow and cannot compete with protonated methanol cation formation at higher internal energies. In fact, the water- and methyl-loss fragment ions appear together and disappear at a ca. 150 meV higher energy in the breakdown diagram. Experiments with selectively deuterated methanol samples showed H scrambling involving two hydroxyl and one methyl hydrogens prior to protonated methanol formation. These insights guided the potential energy surface exploration to rationalize the dissociative photoionization mechanism. The potential energy surface was further validated by a statistical model including isotope effects to fit the experiment for the light and the perdeuterated methanol dimers simultaneously. The (CH3OH)2+ parent ion dissociates via five parallel channels at low internal energies. The loss of both CH2OH and CH3O neutral fragments leads to protonated methanol. However, the latter, direct dissociation channel is energetically forbidden at low energies. Instead, an isomerization transition state is followed by proton transfer from a methyl group, which leads to the CH3(H)OH+⋯CH2OH ion, the precursor to the CH2OH-, H2O-, and CH3-loss fragments after further isomerization steps, in part by a roaming mechanism. Water loss yields the ethanol cation, and two paths are proposed to account for m/z 49 fragment ions after CH3 loss. The roaming pathways are quickly outcompeted by hydrogen bond breaking to yield CH3OH2+, which explains the dominance of the protonated methanol fragment ion in the mass spectrum.
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Affiliation(s)
- Xiangkun Wu
- Paul Scherrer Institute, 5232 Villigen, Switzerland.
| | - Xiaoguo Zhou
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Saša Bjelić
- Paul Scherrer Institute, 5232 Villigen, Switzerland.
| | | | - Bálint Sztáray
- University of the Pacific, Department of Chemistry, Stockton, CA 95211, USA
| | - Andras Bodi
- Paul Scherrer Institute, 5232 Villigen, Switzerland.
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5
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Hartwig B, Suhm MA. Subtle hydrogen bonds: benchmarking with OH stretching fundamentals of vicinal diols in the gas phase. Phys Chem Chem Phys 2021; 23:21623-21640. [PMID: 34580694 DOI: 10.1039/d1cp03367k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The theoretical description of spectral signatures for weakly bound hydrogen contacts between alcohol groups is challenging and remains poorly characterised. By combining Raman jet spectroscopy with appropriately scaled harmonic DFT predictions and relaxation path analyses for 16 vicinal diols (ethylene glycol (ethane-1,2-diol), propane-1,2-diol, 3,3,3-trifluoro-propane-1,2-diol, rac-butane-2,3-diol, 2-methyl-propane-1,2-diol, 2-methyl-butane-2,3-diol, pinacol (2,3-dimethyl-butane-2,3-diol), 3-butene-1,2-diol, 1-phenyl-ethane-1,2-diol, trans-cyclobutane-1,2-diol, trans-cyclopentane-1,2-diol, trans-cyclohexane-1,2-diol, trans-cycloheptane-1,2-diol, cis-cyclohexane-1,2-diol, 1-(1-hydroxy-1-methylethyl)-cyclopentanol and [1,1'-bicyclopentyl]-1,1'-diol), 69 conformational assignments become possible in a two-tier approach with a 5 diol training and an 11 diol test set. The latter reveals systematic deviations for ring strain and secondary π interactions, but otherwise a remarkably robust correction and correlation model based on hybrid DFT with a minimally augmented triple-zeta basis set is obtained, whereas GGA functionals perform significantly worse. Raw experimental data in the 3560-3700 cm-1 wavenumber range as well as computed geometries of all conformations invite further vibrational and structural benchmarking at the onset of hydrogen bonding. Beyond this diol-probed threshold, the accurate prediction of hydrogen bond induced shifts of different magnitudes remains one of the challenges for DFT functionals.
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Affiliation(s)
- Beppo Hartwig
- Institut für Physikalische Chemie, Tammannstr. 6, Göttingen, Germany.
| | - Martin A Suhm
- Institut für Physikalische Chemie, Tammannstr. 6, Göttingen, Germany.
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6
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Halogens in Acetophenones Direct the Hydrogen Bond Docking Preference of Phenol via Stacking Interactions. Molecules 2021; 26:molecules26164883. [PMID: 34443471 PMCID: PMC8400467 DOI: 10.3390/molecules26164883] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/05/2021] [Accepted: 08/09/2021] [Indexed: 11/17/2022] Open
Abstract
Phenol is added to acetophenone (methyl phenyl ketone) and to six of its halogenated derivatives in a supersonic jet expansion to determine the hydrogen bonding preference of the cold and isolated 1:1 complexes by linear infrared spectroscopy. Halogenation is found to have a pronounced effect on the docking site in this intermolecular ketone balance experiment. The spectra unambiguously decide between competing variants of phenyl group stacking due to their differences in hydrogen bond strength. Structures where the phenyl group interaction strongly distorts the hydrogen bond are more difficult to quantify in the experiment. For unsubstituted acetophenone, phenol clearly prefers the methyl side despite a predicted sub-kJ/mol advantage that is nearly independent of zero-point vibrational energy, turning this complex into a challenging benchmark system for electronic structure methods, which include long range dispersion interactions in some way.
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7
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Medel R, Suhm MA. Predicting OH stretching fundamental wavenumbers of alcohols for conformational assignment: different correction patterns for density functional and wave-function-based methods. Phys Chem Chem Phys 2021; 23:5629-5643. [PMID: 33656038 DOI: 10.1039/d1cp00342a] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A model is presented for the prediction of OH stretching fundamental wavenumbers of alcohol conformers in the gas phase by application of a small set of empirical anharmonicity corrections to calculations in the harmonic approximation. In contrast to the popular application of a uniform scaling factor, the local chemical structure of the alcohol is taken into account to greatly improve accuracy. Interestingly, different correction patterns emerge for results of hybrid density functional (B3LYP-D3 and PBE0-D3) and wave-function-based methods (SCS-LMP2, LCCSD(T*)-F12a and CCSD(T)-F12a 1D). This raises questions about electronic structure deficiencies in these methods and differences in anharmonicity between alcohols. After its initial construction on the basis of literature assignments the model is tested with Raman jet spectroscopy of propargyl alcohol, cyclohexanol, borneol, isopinocampheol and 2-methylbutan-2-ol. For propargyl alcohol a spectral splitting attributed to tunneling is resolved. PBE0-D3 is identified as a well performing and broadly affordable electronic structure method for this model. A mean absolute error of 1.3 cm-1 and a maximum absolute error of 3 cm-1 result for 46 conformers of 24 alcohols in a 60 cm-1 range, when a single parameter is adjusted separately for each alcohol substitution class (methanol, primary, secondary, tertiary).
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Affiliation(s)
- Robert Medel
- Institute of Physical Chemistry, University of Goettingen, Tammannstr. 6, 37077 Goettingen, Germany.
| | - Martin A Suhm
- Institute of Physical Chemistry, University of Goettingen, Tammannstr. 6, 37077 Goettingen, Germany.
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8
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Medel R, Suhm MA. Understanding benzyl alcohol aggregation by chiral modification: the pairing step. Phys Chem Chem Phys 2020; 22:25538-25551. [PMID: 33169124 DOI: 10.1039/d0cp04825a] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A combination of linear infrared and Raman spectroscopy in supersonic slit jet expansions is used to clarify the conformational preferences in the dimer of the transiently chiral benzyl alcohol (phenylmethanol) under vacuum isolation. By experimentally exploring close analogies with the permanently chiral 1-phenylethanol, which is conformationally locked in the jet through intramolecular chirality induction, and by computational analysis of their conformational energy landscapes, several conclusions are drawn. The lowest energy dimer is confirmed to be cooperatively OHOHπ-bonded and shown to be homochiral. Its heterochiral counterpart is slightly higher in energy and can be spectrally assigned as a minor constituent. A metastable heterochiral OHπ/OHπ structure with weakly coupled hydrogen bonds is efficiently trapped behind a Ci symmetry-enhanced barrier and can be assigned by IR/Raman mutual exclusion. Its homochiral counterpart is kinetically less stable but might be addressed by rotational spectroscopy. Ratings of standard density functionals with a standard basis set in terms of reproducing these experimental chirality synchronization benchmarks are presented.
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Affiliation(s)
- Robert Medel
- Institute of Physical Chemistry, University of Goettingen, Tammannstr. 6, 37077 Goettingen, Germany.
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9
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Gottschalk HC, Poblotzki A, Fatima M, Obenchain DA, Pérez C, Antony J, Auer AA, Baptista L, Benoit DM, Bistoni G, Bohle F, Dahmani R, Firaha D, Grimme S, Hansen A, Harding ME, Hochlaf M, Holzer C, Jansen G, Klopper W, Kopp WA, Krasowska M, Kröger LC, Leonhard K, Mogren Al-Mogren M, Mouhib H, Neese F, Pereira MN, Prakash M, Ulusoy IS, Mata RA, Suhm MA, Schnell M. The first microsolvation step for furans: New experiments and benchmarking strategies. J Chem Phys 2020; 152:164303. [DOI: 10.1063/5.0004465] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Hannes C. Gottschalk
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Anja Poblotzki
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Mariyam Fatima
- Deutsches Elektronen-Synchrotron, Notkestr. 85, 22607 Hamburg, Germany
| | | | - Cristóbal Pérez
- Deutsches Elektronen-Synchrotron, Notkestr. 85, 22607 Hamburg, Germany
| | - Jens Antony
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstrasse 4, 53115 Bonn, Germany
| | - Alexander A. Auer
- Department of Molecular Theory and Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Leonardo Baptista
- Departamento de Química e Ambiental, Universidade do Estado do Rio de Janeiro, Faculdade de Tecnologia, Resende, RJ, Brazil
| | - David M. Benoit
- Department of Physics and Mathematics, E. A. Milne Centre for Astrophysics and G. W. Gray Centre for Advanced Materials Chemistry, University of Hull, Hull HU6 7RX, United Kingdom
| | - Giovanni Bistoni
- Department of Molecular Theory and Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Fabian Bohle
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstrasse 4, 53115 Bonn, Germany
| | - Rahma Dahmani
- Université Gustave Eiffel, COSYS/LISIS, 5 Blvd. Descartes, 77454 Marne-La-Vallée, France
| | - Dzmitry Firaha
- Lehrstuhl für Technische Thermodynamik, RWTH Aachen University, 52062 Aachen, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstrasse 4, 53115 Bonn, Germany
| | - Andreas Hansen
- Mulliken Center for Theoretical Chemistry, Universität Bonn, Beringstrasse 4, 53115 Bonn, Germany
| | - Michael E. Harding
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Majdi Hochlaf
- Université Gustave Eiffel, COSYS/LISIS, 5 Blvd. Descartes, 77454 Marne-La-Vallée, France
| | - Christof Holzer
- Theoretical Chemistry Group, Institute of Physical Chemistry, Karlsruhe Institute of Technology (KIT), P.O. Box 6980, 76049 Karlsruhe, Germany
| | - Georg Jansen
- Fakultät für Chemie, Universität Duisburg-Essen, Universitätsstr. 5, 45117 Essen, Germany
| | - Wim Klopper
- Theoretical Chemistry Group, Institute of Physical Chemistry, Karlsruhe Institute of Technology (KIT), P.O. Box 6980, 76049 Karlsruhe, Germany
| | - Wassja A. Kopp
- Lehrstuhl für Technische Thermodynamik, RWTH Aachen University, 52062 Aachen, Germany
| | - Małgorzata Krasowska
- Department of Molecular Theory and Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Leif C. Kröger
- Lehrstuhl für Technische Thermodynamik, RWTH Aachen University, 52062 Aachen, Germany
| | - Kai Leonhard
- Lehrstuhl für Technische Thermodynamik, RWTH Aachen University, 52062 Aachen, Germany
| | - Muneerah Mogren Al-Mogren
- Chemistry Department, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Kingdom of Saudi Arabia
| | - Halima Mouhib
- Université Gustave Eiffel, COSYS/LISIS, 5 Blvd. Descartes, 77454 Marne-La-Vallée, France
| | - Frank Neese
- Department of Molecular Theory and Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Max N. Pereira
- Departamento de Química e Ambiental, Universidade do Estado do Rio de Janeiro, Faculdade de Tecnologia, Resende, RJ, Brazil
| | - Muthuramalingam Prakash
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - Inga S. Ulusoy
- Theoretical Chemistry, Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
| | - Ricardo A. Mata
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Martin A. Suhm
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Melanie Schnell
- Deutsches Elektronen-Synchrotron, Notkestr. 85, 22607 Hamburg, Germany
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10
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Meyer KAE, Davies JA, Ellis AM. Shifting formic acid dimers into perspective: vibrational scrutiny in helium nanodroplets. Phys Chem Chem Phys 2020; 22:9637-9646. [DOI: 10.1039/d0cp01060j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A metastable dimer of formic acid has been prepared inside superfluid helium nanodroplets and examined using IR spectroscopy and quantum chemical calculations.
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Affiliation(s)
- Katharina A. E. Meyer
- Institut für Physikalische Chemie
- Georg-August-Universität Göttingen
- 37077 Göttingen
- Germany
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11
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Abstract
AbstractFormic acid dimer as the prototypical doubly hydrogen-bonded gas-phase species is discussed from the perspective of the three translational and the three rotational degrees of freedom which are lost when two formic acid molecules form a stable complex. The experimental characterisation of these strongly hindered translations and rotations is reviewed, as are attempts to describe the associated fundamental vibrations, their combinations, and their thermal shifts by different electronic structure calculations and vibrational models. A remarkable match is confirmed for the combination of a CCSD(T)-level harmonic treatment and an MP2-level anharmonic VPT2 correction. Qualitatively correct thermal shifts of the vibrational spectra can be obtained from classical molecular dynamics in CCSD(T)-quality force fields. A detailed analysis suggests that this agreement between experiment and composite theoretical treatment is not strongly affected by fortuitous error cancellation but fully converged variational treatments of the six pair or intermolecular modes and their overtones and combinations in this model system would be welcome.
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12
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Oswald S, Suhm MA. Soft experimental constraints for soft interactions: a spectroscopic benchmark data set for weak and strong hydrogen bonds. Phys Chem Chem Phys 2019; 21:18799-18810. [PMID: 31453998 DOI: 10.1039/c9cp03651b] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An experimental benchmark data base on rotational constants, vibrational properties and energy differences for weakly and more strongly hydrogen-bonded complexes and their constituents from the spectroscopic literature is assembled. It is characterized in detail and finally contracted to a more compact, discriminatory set (ENCH-51, for Experimental Non-Covalent Harmonic with 51 entries). The meeting points between theory and experiment consist of equilibrium rotational constants and harmonic frequencies and energies, which are back-corrected from experimental observables and are very easily accessible by quantum chemical calculations. The relative performance of B3LYP-D3, PBE0-D3 and M06-2X density functional theory predictions with a quadruple-zeta basis set is used to illustrate systematic errors, error compensation and selective performance for structural, vibrational and energetical observables. The current focus is on perspectives and different benchmarking methodologies, rather than on a specific theoretical method or a specific class of compounds. Extension of the data base in chemical, observable and quantum chemical method space is encouraged.
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Affiliation(s)
- Sönke Oswald
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany.
| | - Martin A Suhm
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, 37077 Göttingen, Germany.
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13
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Williams IM, Qasim LN, Tran L, Scott A, Riley K, Dutta S. C-D Vibration at C2 Position of Imidazolium Cation as a Probe of the Ionic Liquid Microenvironment. J Phys Chem A 2019; 123:6342-6349. [PMID: 31257885 DOI: 10.1021/acs.jpca.9b02387] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Unlike molecular solvents, imidazolium-based ionic liquids are entirely made of ions with spatial heterogeneity. There is a need for spectroscopic probes that can assess the microenvironment near the cations of these complex liquids. In this manuscript, we describe simple chemical procedures to label the C2 position of imidazolium cation with a C-D vibrational probe and show, through linear and nonlinear vibrational spectroscopies, that this C-D stretching mode can be a useful analytical tool to assess both the solvent microenvironment and solute-solvent interactions in imidazolium-based ionic liquids from the cation point of view. It is expected that this C-D vibration probe on the cation will lead to the development of innovative experimental strategies that can provide a better understanding of such ionic liquids.
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Affiliation(s)
- Isis Marie Williams
- Department of Chemistry , Xavier University of Louisiana , New Orleans , Louisiana 70125 , United States
| | - Layla N Qasim
- Department of Chemistry , Tulane University , New Orleans , Louisiana 70118 , United States
| | - Ly Tran
- Department of Chemistry , Xavier University of Louisiana , New Orleans , Louisiana 70125 , United States
| | - Asia Scott
- Department of Chemistry , Xavier University of Louisiana , New Orleans , Louisiana 70125 , United States
| | - Kevin Riley
- Department of Chemistry , Xavier University of Louisiana , New Orleans , Louisiana 70125 , United States
| | - Samrat Dutta
- Department of Chemistry , Xavier University of Louisiana , New Orleans , Louisiana 70125 , United States
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14
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Forsting T, Zischang J, Suhm MA, Eckhoff M, Schröder B, Mata RA. Strained hydrogen bonding in imidazole trimer: a combined infrared, Raman, and theory study. Phys Chem Chem Phys 2019; 21:5989-5998. [DOI: 10.1039/c9cp00399a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This is not how three imidazole molecules prefer to arrange, as a combined IR, Raman and computational analysis unambiguously shows.
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Affiliation(s)
- Thomas Forsting
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
| | - Julia Zischang
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
| | - Martin A. Suhm
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
| | - Marco Eckhoff
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
| | - Benjamin Schröder
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
| | - Ricardo A. Mata
- Institut für Physikalische Chemie
- Universität Göttingen
- 37077 Göttingen
- Germany
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15
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Siebrand W, Smedarchina Z, Ferro-Costas D, Martínez-Núñez E, Fernández-Ramos A. Reply to the 'Comment on "Methanol dimer formation drastically enhances hydrogen abstraction from methanol by OH at low temperature"' by D. Heard, R. Shannon, J. Gomez Martin, R. Caravan, M. Blitz, J. Plane, M. Antiñolo, M. Agundez, E. Jimenez, B. Ballesteros, A. Canosa, G. El Dib, J. Albaladejo and J. Cernicharo, Phys. Chem. Chem. Phys., 2018, 20, DOI: 10.1039/C7CP04561A. Phys Chem Chem Phys 2018; 20:8355-8357. [PMID: 29498727 DOI: 10.1039/c8cp00519b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this Reply we answer the two main arguments raised in the Comment. The first argument is related to the binding energy of the methanol dimer and its influence on the dimerization rate constant. We show that the dimerization rate constants calculated in the Comment are unphysically low. We report values that are about two orders of magnitude higher than the values of the Comment, which confirm the conclusions of the original article that dimers can be present in a small amount. The second argument based on the dependence of the pseudo-first order rates on the methanol concentration was already explained in detail in the Supporting Information of the original article.
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Affiliation(s)
- W Siebrand
- National Research Council of Canada, Ontario K1A 0R6, Canada
| | - Z Smedarchina
- National Research Council of Canada, Ontario K1A 0R6, Canada
| | - D Ferro-Costas
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
| | - E Martínez-Núñez
- Departamento de Química Física, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - A Fernández-Ramos
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
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16
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Shannon RJ, Gómez Martín JC, Caravan RL, Blitz MA, Plane JMC, Heard DE, Antiñolo M, Agúndez M, Jiménez E, Ballesteros B, Canosa A, El Dib G, Albaladejo J, Cernicharo J. Comment on “Methanol dimer formation drastically enhances hydrogen abstraction from methanol by OH at low temperature” by W. Siebrand, Z. Smedarchina, E. Martínez-Núñez and A. Fernández-Ramos, Phys. Chem. Chem. Phys., 2016, 18, 22712. Phys Chem Chem Phys 2018; 20:8349-8354. [DOI: 10.1039/c7cp04561a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A low fraction of methanol dimers is formed in the Laval nozzle used for kinetics studies at very low temperatures.
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17
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Mata RA, Suhm MA. Benchmarking Quantum Chemical Methods: Are We Heading in the Right Direction? Angew Chem Int Ed Engl 2017; 56:11011-11018. [PMID: 28452424 PMCID: PMC5582598 DOI: 10.1002/anie.201611308] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/20/2016] [Indexed: 11/15/2022]
Abstract
Theoreticians and experimentalists should work together more closely to establish reliable rankings and benchmarks for quantum chemical methods. Comparison to carefully designed experimental benchmark data should be a priority. Guidelines to improve the situation for experiments and calculations are proposed.
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Affiliation(s)
- Ricardo A. Mata
- Institut für Physikalische ChemieUniversität GöttingenTammannstrasse 637077GöttingenGermany
| | - Martin A. Suhm
- Institut für Physikalische ChemieUniversität GöttingenTammannstrasse 637077GöttingenGermany
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18
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Oswald S, Suhm MA. Experimental Reference Data for Hexafluorinated Propanol by Exploring an Unusual Intermolecular Torsional Balance. Angew Chem Int Ed Engl 2017; 56:12672-12676. [DOI: 10.1002/anie.201705301] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/26/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Sönke Oswald
- Institute of Physical Chemistry University of Goettingen Tammannstr. 6 37077 Goettingen Germany
| | - Martin A. Suhm
- Institute of Physical Chemistry University of Goettingen Tammannstr. 6 37077 Goettingen Germany
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19
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Oswald S, Suhm MA. Experimental Reference Data for Hexafluorinated Propanol by Exploring an Unusual Intermolecular Torsional Balance. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201705301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Sönke Oswald
- Institute of Physical Chemistry University of Goettingen Tammannstr. 6 37077 Goettingen Germany
| | - Martin A. Suhm
- Institute of Physical Chemistry University of Goettingen Tammannstr. 6 37077 Goettingen Germany
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20
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Oswald S, Wallrabe M, Suhm MA. Cooperativity in Alcohol-Nitrogen Complexes: Understanding Cryomatrices through Slit Jet Expansions. J Phys Chem A 2017; 121:3411-3422. [PMID: 28443670 DOI: 10.1021/acs.jpca.7b01265] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
FTIR spectroscopy of supersonic expansions is used to characterize alcohol dimers with one, two, and several nitrogen molecules attached to them. The nitrogen coating causes progressive spectral downshifts of the OH stretching fundamentals which are related to and explain matrix isolation shifts. Comparison of methanol, tert-butyl alcohol and ethanol as well as deuteration of methanol assist in the assignment. Alcohol monomers and trimers are significantly more resistant to nitrogen coating due to a lack of cooperativity and dangling bonds, respectively. In the case of ethanol, the role of conformational isomerism and combination bands is further elucidated. The experimental findings help rationalize the anomalously small OH stretching dimerization shift of methanol in the gas phase, in comparison to that of tert-butyl alcohol.
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Affiliation(s)
- Sönke Oswald
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstraße 6, 37077 Göttingen, Germany
| | - Mareike Wallrabe
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstraße 6, 37077 Göttingen, Germany
| | - Martin A Suhm
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstraße 6, 37077 Göttingen, Germany
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21
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Mata RA, Suhm MA. Quantenchemische Methoden im Leistungsvergleich: Stimmt die Richtung noch? Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611308] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ricardo A. Mata
- Institut für Physikalische Chemie; Universität Göttingen; Tammannstraße 6 37077 Göttingen Deutschland
| | - Martin A. Suhm
- Institut für Physikalische Chemie; Universität Göttingen; Tammannstraße 6 37077 Göttingen Deutschland
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22
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Sulaiman MI, Yang S, Ellis AM. Infrared Spectroscopy of Methanol and Methanol/Water Clusters in Helium Nanodroplets: The OH Stretching Region. J Phys Chem A 2017; 121:771-776. [DOI: 10.1021/acs.jpca.6b11170] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Media I. Sulaiman
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K
| | - Shengfu Yang
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K
| | - Andrew M. Ellis
- Department of Chemistry, University of Leicester, University Road, Leicester, LE1 7RH, U.K
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23
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Asselin P, Madebène B, Soulard P, Georges R, Goubet M, Huet TR, Pirali O, Zehnacker-Rentien A. Competition between inter- and intra-molecular hydrogen bonding: An infrared spectroscopic study of jet-cooled amino-ethanol and its dimer. J Chem Phys 2016; 145:224313. [DOI: 10.1063/1.4972016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Pierre Asselin
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, F-75005 Paris, France
- CNRS, UMR 8233, MONARIS, F-75005 Paris, France
| | - Bruno Madebène
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, F-75005 Paris, France
- CNRS, UMR 8233, MONARIS, F-75005 Paris, France
| | - Pascale Soulard
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8233, MONARIS, F-75005 Paris, France
- CNRS, UMR 8233, MONARIS, F-75005 Paris, France
| | - Robert Georges
- Institut de Physique de Rennes, Campus de Beaulieu, Bat 11C, UMR 6251, Université de Rennes 1-CNRS, 35042 Rennes Cedex, France
| | - Manuel Goubet
- Université Lille, CNRS, UMR 8523—PhLAM–Physique des Lasers, Atomes et Molécules, F-59000 Lille, France
| | - Thérèse R. Huet
- Université Lille, CNRS, UMR 8523—PhLAM–Physique des Lasers, Atomes et Molécules, F-59000 Lille, France
| | - Olivier Pirali
- Institut des Sciences Moléculaires d’Orsay (ISMO), CNRS, University of Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
- Ligne AILES — Synchrotron SOLEIL, L’Orme des Merisiers, F-91192 Gif-sur-Yvette Cedex, France
| | - Anne Zehnacker-Rentien
- Institut des Sciences Moléculaires d’Orsay (ISMO), CNRS, University of Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
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24
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Mackeprang K, Xu ZH, Maroun Z, Meuwly M, Kjaergaard HG. Spectroscopy and dynamics of double proton transfer in formic acid dimer. Phys Chem Chem Phys 2016; 18:24654-62. [PMID: 27545453 DOI: 10.1039/c6cp03462d] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We present the isolated gas phase infrared spectra of formic acid dimer, (HCOOH)2, and its deuterated counterpart formic-d acid, (DCOOH)2, at room temperature. The formic acid dimer spectrum was obtained by spectral subtraction of a spectrum of formic acid vapor recorded at low pressure from that recorded at a higher pressure. The spectra of formic acid vapor contain features from both formic acid monomer and formic acid dimer, but at low and high pressures of formic acid, the equilibrium is pushed towards the monomer and dimer, respectively. A similar approach was used for the formic-d acid dimer. Building on the previous development of the Molecular Mechanics with Proton Transfer (MMPT) force field for simulating proton transfer reactions, molecular dynamics (MD) simulations were carried out to interpret the experimental spectra in the OH-stretching region. Within the framework of MMPT, a combination of symmetric single and double minimum potential energy surfaces (PESs) provides a good description of the double proton transfer PES. In a next step, potential morphing together with electronic structure calculations at the B3LYP and MP2 level of theory was used to align the computed and experimentally observed spectral features in the OH-stretching region. From this analysis, a barrier for double proton transfer between 5 and 7 kcal mol(-1) was derived, which compares with a CCSD(T)/aug-cc-pVTZ calculated barrier of 7.9 kcal mol(-1). Such a combination of experimental and computational techniques for estimating barriers for proton transfer in gas phase systems is generic and holds promise for further improved PESs and energetics of these important systems. Additional MD simulations at the semi-empirical DFTB level of theory agree quite well for the center band position but underestimate the width of the OH-stretching band.
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Affiliation(s)
- Kasper Mackeprang
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
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25
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Kollipost F, Otto KE, Suhm MA. A Symmetric Recognition Motif between Vicinal Diols: The Fourfold Grip in Ethylene Glycol Dimer. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Franz Kollipost
- Institut für Physikalische Chemie; Georg-August-Universität Göttingen; Tammannstr. 6 37077 Göttingen Germany
| | - Katharina E. Otto
- Institut für Physikalische Chemie; Georg-August-Universität Göttingen; Tammannstr. 6 37077 Göttingen Germany
| | - Martin A. Suhm
- Institut für Physikalische Chemie; Georg-August-Universität Göttingen; Tammannstr. 6 37077 Göttingen Germany
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26
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Kollipost F, Otto KE, Suhm MA. A Symmetric Recognition Motif between Vicinal Diols: The Fourfold Grip in Ethylene Glycol Dimer. Angew Chem Int Ed Engl 2016; 55:4591-5. [PMID: 26929113 PMCID: PMC5069640 DOI: 10.1002/anie.201600603] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 11/08/2022]
Abstract
Ethylene glycol has a transiently chiral, asymmetric global minimum structure, but it favors a highly symmetric, achiral dimer arrangement which has not been considered or found in previous quantum‐chemical studies. Complementary FTIR and Raman spectroscopy in supersonic jets allows for the detection and straightforward assignment of this four‐fold hydrogen‐bonded dimer, which introduces an interesting supramolecular binding motif for vicinal diols and provides a strong case for transient chirality synchronization.
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Affiliation(s)
- Franz Kollipost
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr. 6, 37077, Göttingen, Germany
| | - Katharina E Otto
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr. 6, 37077, Göttingen, Germany
| | - Martin A Suhm
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen, Tammannstr. 6, 37077, Göttingen, Germany.
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27
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Heger M, Andersen J, Suhm MA, Wugt Larsen R. The donor OH stretching–libration dynamics of hydrogen-bonded methanol dimers in cryogenic matrices. Phys Chem Chem Phys 2016; 18:3739-45. [DOI: 10.1039/c5cp07387a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
FTIR spectra of the methanol dimer trapped in neon matrices are presented.
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Affiliation(s)
- M. Heger
- Institut für Physikalische Chemie
- Universität Göttingen
- D-37077 Göttingen
- Germany
| | - J. Andersen
- Department of Chemistry
- Technical University of Denmark
- DK-2800 Kgs. Lyngby
- Denmark
| | - M. A. Suhm
- Institut für Physikalische Chemie
- Universität Göttingen
- D-37077 Göttingen
- Germany
| | - R. Wugt Larsen
- Department of Chemistry
- Technical University of Denmark
- DK-2800 Kgs. Lyngby
- Denmark
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28
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Heger M, Mata RA, Suhm MA. Soft hydrogen bonds to alkenes: the methanol-ethene prototype under experimental and theoretical scrutiny. Chem Sci 2015; 6:3738-3745. [PMID: 29218143 PMCID: PMC5707488 DOI: 10.1039/c5sc01002k] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 04/23/2015] [Indexed: 02/05/2023] Open
Abstract
An FTIR spectroscopic study of the elusive hydrogen-bonded methanol-ethene complex, the most elementary example for weak intermolecular alcohol hydrogen bonding to a π cloud, is presented. By isolating the complex in a supersonic jet, the rigorous comparability to high-level quantum chemical calculations is ensured. In stark contrast to classical hydrogen bonds, experimental overtone analysis reveals the harmonic oscillator approximation for the OH red shift to be accurate. Harmonic calculations up to explicitly correlated local coupled-cluster level are thus found to agree very well with experiment. The experimental OH values for the red shift (45 cm-1), the small change in diagonal anharmonicity (-3 cm-1) and the overtone intensity attenuation (2 × 102-fold) together with theoretical predictions for the preferred structural arrangement and the zero-point-corrected dissociation energy (8 kJ mol-1) may thus be regarded as definitive reference values for related systems and for more approximate computational methods. In particular, MP2 calculations are shown to fail for this kind of weak intermolecular interaction.
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Affiliation(s)
- Matthias Heger
- Institut für Physikalische Chemie , Universität Göttingen , Tammannstr. 6 , 37077 Göttingen , Germany .
| | - Ricardo A Mata
- Institut für Physikalische Chemie , Universität Göttingen , Tammannstr. 6 , 37077 Göttingen , Germany .
| | - Martin A Suhm
- Institut für Physikalische Chemie , Universität Göttingen , Tammannstr. 6 , 37077 Göttingen , Germany .
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29
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Heger M, Altnöder J, Poblotzki A, Suhm MA. To π or not to π – how does methanol dock onto anisole? Phys Chem Chem Phys 2015; 17:13045-52. [DOI: 10.1039/c5cp01545f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Supersonic jet spectroscopy reveals that methanol opts against aromatic docking onto anisole despite a very close competition.
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Affiliation(s)
- Matthias Heger
- Institut für Physikalische Chemie
- Georg-August-Universität Göttingen
- D-37077 Göttingen
- Germany
| | - Jonas Altnöder
- Institut für Physikalische Chemie
- Georg-August-Universität Göttingen
- D-37077 Göttingen
- Germany
| | - Anja Poblotzki
- Institut für Physikalische Chemie
- Georg-August-Universität Göttingen
- D-37077 Göttingen
- Germany
| | - Martin A. Suhm
- Institut für Physikalische Chemie
- Georg-August-Universität Göttingen
- D-37077 Göttingen
- Germany
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30
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Kollipost F, Andersen J, Mahler DW, Heimdal J, Heger M, Suhm MA, Wugt Larsen R. The effect of hydrogen bonding on torsional dynamics: A combined far-infrared jet and matrix isolation study of methanol dimer. J Chem Phys 2014; 141:174314. [DOI: 10.1063/1.4900922] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- F. Kollipost
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, D-37077 Göttingen, Germany
| | - J. Andersen
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, DK-2800 Kgs. Lyngby, Denmark
| | - D. W. Mahler
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, DK-2800 Kgs. Lyngby, Denmark
| | - J. Heimdal
- MAX-IV Laboratory, Lund University, P. O. Box 118, SE-22100 Lund, Sweden
| | - M. Heger
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, D-37077 Göttingen, Germany
| | - M. A. Suhm
- Institut für Physikalische Chemie, Universität Göttingen, Tammannstr. 6, D-37077 Göttingen, Germany
| | - R. Wugt Larsen
- Department of Chemistry, Technical University of Denmark, Kemitorvet 206, DK-2800 Kgs. Lyngby, Denmark
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