1
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Jin J, Wulf T, Jorewitz M, Heine T, Asmis KR. Vibrational spectroscopy of Cu +(H 2) 4: about anharmonicity and fluxionality. Phys Chem Chem Phys 2023; 25:5262-5270. [PMID: 36723211 DOI: 10.1039/d2cp05802b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The vibrational spectra of the copper(I) cation-dihydrogen complexes Cu+(H2)4, Cu+(D2)4 and Cu+(D2)3H2 are studied using cryogenic ion trap vibrational spectroscopy in combination with quantum chemical calculations. The infrared photodissociation (IRPD) spectra (2500-7300 cm-1) are assigned based on a comparison to IR spectra calculated using vibrational second-order perturbation theory (VPT2). The IRPD spectra exhibit ≈60 cm-1 broad bands that lack rotational resolution, indicative of rather floppy complexes even at an ion trap temperature of 10 K. The observed vibrational features are assigned to the excitations of dihydrogen stretching fundamentals, combination bands of these fundamentals with low energy excitations as well as overtone excitations of a minimum-energy structure with Cs symmetry. The three distinct dihydrogen positions present in the structure can interconvert via pseudorotations with energy barriers less than 10 cm-1, far below the zero-point vibrational energy. Ab initio Born-Oppenheimer molecular dynamics (BOMD) simulations confirm the fluxional behavior of these complexes and yield an upper limit for the timeframe of the pseudorotation on the order of 10 ps. For Cu+(D2)3H2, the H2 and D2 loss channels yield different IRPD spectra indicating non-ergodic behavior.
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Affiliation(s)
- Jiaye Jin
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
| | - Toshiki Wulf
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany. .,Institute of Resource Ecology, Research Site Leipzig, Helmholtz-Zentrum Dresden-Rossendorf, Permoserstr. 15, 04318, Leipzig, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, TU Dresden, 01062, Dresden, Germany.
| | - Marcel Jorewitz
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
| | - Thomas Heine
- Institute of Resource Ecology, Research Site Leipzig, Helmholtz-Zentrum Dresden-Rossendorf, Permoserstr. 15, 04318, Leipzig, Germany.,Faculty of Chemistry and Food Chemistry, School of Science, TU Dresden, 01062, Dresden, Germany.
| | - Knut R Asmis
- Wilhelm-Ostwald-Institut für Physikalische und Theoretisch Chemie, Universität Leipzig, Linnéstr. 2, 04103, Leipzig, Germany.
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2
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Wagner JP, McDonald DC, Colley JE, Franke PR, Duncan MA. Infrared spectroscopy of the protonated HCl dimer and trimer. J Chem Phys 2021; 155:134302. [PMID: 34624978 DOI: 10.1063/5.0065477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The protonated HCl dimer and trimer complexes were prepared by pulsed discharges in supersonic expansions of helium or argon doped with HCl and hydrogen. The ions were mass selected in a reflectron time-of-flight spectrometer and investigated with photodissociation spectroscopy in the IR and near-IR regions. Anharmonic vibrational frequencies were computed with VPT2 at the MP2/cc-pVTZ level of theory. The Cl-H stretching fundamentals and overtones were measured in addition to stretch-torsion combinations. VPT2 theory at this level confirms the proton-bound structure of the dimer complex and provides a reasonably good description of the anharmonic vibrations in this system. The trimer has a HCl-HClH+-ClH structure in which a central chloronium ion is solvated by two HCl molecules via hydrogen bonding. VPT2 reproduces anharmonic frequencies for this system, including several combinations involving core ion Cl-H stretches, but fails to describe the relative band intensities.
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Affiliation(s)
- J Philipp Wagner
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - David C McDonald
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - Jason E Colley
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - Peter R Franke
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - Michael A Duncan
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
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3
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McDonald DC, Rittgers BM, Theis RA, Fortenberry RC, Marks JH, Leicht D, Duncan MA. Infrared spectroscopy and anharmonic theory of H 3 +Ar 2,3 complexes: The role of symmetry in solvation. J Chem Phys 2020; 153:134305. [PMID: 33032436 DOI: 10.1063/5.0023205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vibrational spectra of H3 +Ar2,3 and D3 +Ar2,3 are investigated in the 2000 cm-1 to 4500 cm-1 region through a combination of mass-selected infrared laser photodissociation spectroscopy and computational work including the effects of anharmonicity. In the reduced symmetry of the di-argon complex, vibrational activity is detected in the regions of both the symmetric and antisymmetric hydrogen stretching modes of H3 +. The tri-argon complex restores the D3h symmetry of the H3 + ion, with a concomitant reduction in the vibrational activity that is limited to the region of the antisymmetric stretch. Throughout these spectra, additional bands are detected beyond those predicted with harmonic vibrational theory. Anharmonic theory is able to reproduce some of the additional bands, with varying degrees of success.
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Affiliation(s)
- D C McDonald
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - B M Rittgers
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - R A Theis
- Department of Chemistry and Biochemistry, Georgia Southern University, Statesboro, Georgia 30460, USA
| | - R C Fortenberry
- Department of Chemistry and Biochemistry, University of Mississippi, University, Mississippi 38677, USA
| | - J H Marks
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - D Leicht
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - M A Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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Leicht D, Rittgers BM, Douberly GE, Wagner JP, McDonald DC, Mauney DT, Tsuge M, Lee YP, Duncan MA. Infrared spectroscopy of H+(CO)2 in the gas phase and in para-hydrogen matrices. J Chem Phys 2020; 153:084305. [DOI: 10.1063/5.0019731] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Daniel Leicht
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | | | - Gary E. Douberly
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J. Philipp Wagner
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - David C. McDonald
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Daniel T. Mauney
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Masashi Tsuge
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan
- Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
| | - Yuan-Pern Lee
- Department of Applied Chemistry, National Chiao Tung University, Hsinchu 30010, Taiwan
- Center for Emergent Functional Matter Science, National Chiao Tung University, Hsinchu 30010, Taiwan
- Institute of Atomic and Molecular Sciences Academia Sinica, Taipei 10617, Taiwan
| | - Michael A. Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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5
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Boyer MA, Chiu CS, McDonald DC, Wagner JP, Colley JE, Orr DS, Duncan MA, McCoy AB. The Role of Tunneling in the Spectra of H 5+ and D 5+ up to 7300 cm -1. J Phys Chem A 2020; 124:4427-4439. [PMID: 32392420 DOI: 10.1021/acs.jpca.0c02299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The spectra for H5+ and D5+ are extended to cover the region between 4830 and 7300 cm-1. These spectra are obtained using mass-selected photodissociation spectroscopy. To understand the nature of the states that are accessed by the transitions in this and prior studies, we develop a four-dimensional model Hamiltonian. This Hamiltonian is expressed in terms of the two outer H2 stretches, the displacement of the shared proton from the center of mass of these two H2 groups, and the distance between the H2 groups. This choice is motivated by the large oscillator strength associated with the shared proton stretch and the fact that the spectral regions that have been probed correspond to zero, one, and two quanta of excitation in the H2 stretches. This model is analyzed using an adiabatic separation of the H2 stretches from the other two vibrations and includes the non-adiabatic couplings between H2 stretch states with the same total number of quanta of excitation in the H2 stretches. Based on the analysis of the energies and wave functions obtained from this model, we find that when there are one or more quanta of excitation in the H2 stretches the states come in pairs that reflect tunneling doublets. The states accessed by the transitions in the spectrum with the largest intensity are assigned to the members of the doublets with requisite symmetry that are localized on the lowest-energy adiabat for a given level of H2 excitation.
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Affiliation(s)
- Mark A Boyer
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Chloe S Chiu
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - David C McDonald
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - J Philipp Wagner
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Jason E Colley
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Dylan S Orr
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Michael A Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Anne B McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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Prosmiti R, Valdés Á. The smallest proton-bound dimer H 5+: theoretical progress. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2019; 377:20180396. [PMID: 31378176 PMCID: PMC6710890 DOI: 10.1098/rsta.2018.0396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/19/2019] [Indexed: 06/10/2023]
Abstract
The protonated hydrogen dimer, H5+, is the smallest system including proton transfer, and has been of long-standing interest since its first laboratory observation in 1962. H5+ and its isotopologues are the intermediate complexes in deuterium fractionation reactions, and are of central importance in molecular astrophysics. The recently recorded infrared spectra of both H5+ and D5+ reveal a rich vibrational dynamics of the cations, which presents a challenge for standard theoretical approaches. Although H5+ is a four-electron ion, which makes highly accurate electronic structure calculations tractable, the construction of ab initio-based potential energy and dipole moment surfaces has proved a hard task. In the same vein, the difficulties in treating the nuclear motion could also become cumbersome due to their high dimensionality, floppiness and/or symmetry. These systems are prototypical examples for studying large-amplitude motions, as they are highly delocalized, interconverting between equivalent minima through internal rotation and proton transfer motions requiring state-of-the-art treatments. Recent advances in the computational vibrational spectroscopy of the H5+ cation and its isotopologues are reported from full quantum spectral simulations, providing important information in a rigorous manner, and open perspectives for further future investigations. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.
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Affiliation(s)
- Rita Prosmiti
- Departamento PAMS, Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain
| | - Álvaro Valdés
- Departamento de Física, Universidad Nacional de Colombia, Calle 26, Cra 39, Edificio 404, Bogotá, Colombia
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Császár AG, Fábri C, Sarka J. Quasistructural molecules. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1432] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry ELTE Eötvös Loránd University Budapest Hungary
- MTA‐ELTE Complex Chemical Systems Research Group Budapest Hungary
| | - Csaba Fábri
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry ELTE Eötvös Loránd University Budapest Hungary
- MTA‐ELTE Complex Chemical Systems Research Group Budapest Hungary
| | - János Sarka
- Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas USA
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Tan JA, Kuo JL. A theoretical study on the infrared signatures of proton-bound rare gas dimers (Rg-H +-Rg), Rg = {Ne, Ar, Kr, and Xe}. J Chem Phys 2019; 150:124305. [PMID: 30927880 DOI: 10.1063/1.5090031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The infrared spectrum of proton-bound rare gas dimers has been extensively studied via matrix isolation spectroscopy. However, little attention has been paid on their spectrum in the gas phase. Most of the Rg2H+ has not been detected outside the matrix environment. Recently, ArnH+ (n = 3-7) has been first detected in the gas-phase [D. C. McDonald et al., J. Chem. Phys. 145, 231101 (2016)]. In that work, anharmonic theory can reproduce the observed vibrational structure. In this paper, we extend the existing theory to examine the vibrational signatures of Rg2H+, Rg = {Ne, Ar, Kr, and Xe}. The successive binding of Rg to H+ was investigated through the calculation of stepwise formation energies. It was found that this binding is anti-cooperative. High-level full-dimensional potential energy surfaces at the CCSD(T)/aug-cc-pVQZ//MP2/aug-cc-pVQZ were constructed and used in the anharmonic calculation via discrete variable representation. We found that the potential coupling between the symmetric and asymmetric Rg-H+ stretch (ν1 and ν3 respectively) causes a series of bright n1ν1 + ν3 progressions. From Ne2H+ to Xe2H+, an enhancement of intensities for these bands was observed.
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Affiliation(s)
- Jake A Tan
- Institute of Atomic and Molecular Sciences, Academia Sinica, No. 1 Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | - Jer-Lai Kuo
- Institute of Atomic and Molecular Sciences, Academia Sinica, No. 1 Roosevelt Road, Section 4, Taipei 10617, Taiwan
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9
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McDonald DC, Wagner JP, Duncan MA. Communication: Infrared photodissociation spectroscopy of the H 6+ cation in the gas phase. J Chem Phys 2018; 149:031105. [PMID: 30037249 DOI: 10.1063/1.5043425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The H6+ cation was generated in a pulsed-discharge supersonic expansion of hydrogen and mass-selected in a time-of-flight spectrometer. Its vibrational spectrum was measured in the region of 2050-4550 cm-1 using infrared photodissociation with a tunable OPO/OPA laser system. The H6+ photodissociates, producing H5+, H4+, and H3+ fragments; each of these fragment channels has a different spectrum. Computational studies identify two low-lying isomers described in previous work, whose energies were evaluated at the CCSD(T)/cc-pVTZ//MP2/cc-pVTZ level of theory. A D2d species having an H2+ cation bridging between two perpendicular H2 molecules is the global minimum structure. A Cs structure with an H3+ core ion bound to both H2 and an H atom lies 4.0 kcal mol-1 higher in energy. Anharmonic vibrational spectra were computed for each of these isomers with second-order vibrational perturbation theory (VPT2) in combination with density functional theory at the B2PLYP/cc-pVTZ level. The comparison between experimental and predicted spectra confirms the presence of both the D2d and Cs structures and explains the spectra in different fragmentation channels. Although we find reasonable agreement between the experiment and the spectra predicted by VPT2 computations, a more sophisticated computational approach is needed to better understand this complex system.
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Affiliation(s)
- David C McDonald
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J Philipp Wagner
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - Michael A Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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10
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Wagner JP, McDonald DC, Duncan MA. Spectroscopy of Proton Coordination with Ethylenediamine. J Phys Chem A 2018; 122:5168-5176. [PMID: 29771517 DOI: 10.1021/acs.jpca.8b03592] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protonated ethylenediamine monomer, dimer, and trimer were produced in the gas phase by an electrical discharge/supersonic expansion of argon seeded with ethylenediamine (C2H8N2, en) vapor. Infrared spectra of these ions were measured in the region from 1000 to 4000 cm-1 using laser photodissociation and argon tagging. Computations at the CBS-QB3 level were performed to explore possible isomers and understand the infrared spectra. The protonated monomer exhibits a gauche conformation and an intramolecular hydrogen bond. Its parallel shared proton vibration occurs as a broad band around 2785 cm-1, despite the formally equivalent proton affinities of the two amino groups involved, which usually leads to low frequency bands. The barrier to intramolecular proton transfer is 2.2 kcal mol-1 and does not vanish upon addition of the zero-point energy, unlike the related protonated ammonia dimer. The structure of the dimer is formed by chelation of the monomer's NH3+ group, thereby localizing the excess proton and increasing the frequency of the intramolecular shared proton vibration to 3157 cm-1. Other highly fluxional dimer structures with facile intermolecular proton transfer and concomitant structural reorganization were computed to lie within 2 kcal mol-1 of the experimentally observed structure. The spectrum of the trimer is rather diffuse, and a clear assignment is not possible. However, an isomer with an intramolecular proton transfer like that of the monomer is most consistent with the experimental spectrum.
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Affiliation(s)
- J Philipp Wagner
- Department of Chemistry , University of Georgia , 140 Cedar Street , Athens , Georgia 30602 , United States
| | - David C McDonald
- Department of Chemistry , University of Georgia , 140 Cedar Street , Athens , Georgia 30602 , United States
| | - Michael A Duncan
- Department of Chemistry , University of Georgia , 140 Cedar Street , Athens , Georgia 30602 , United States
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11
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Mid/near infrared spectroscopy of the H2Cl+Ar cation complex compared to the predictions of anharmonic theory. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2017.10.056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Wagner JP, McDonald DC, Duncan MA. Infrared Spectroscopy of the Astrochemically Relevant Protonated Formaldehyde Dimer. J Phys Chem A 2017; 122:192-198. [DOI: 10.1021/acs.jpca.7b10573] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. Philipp Wagner
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
| | - David C. McDonald
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
| | - Michael A. Duncan
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, United States
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13
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Mauney DT, Maner JA, Duncan MA. IR Spectroscopy of Protonated Acetylacetone and Its Water Clusters: Enol-Keto Tautomers and Ion→Solvent Proton Transfer. J Phys Chem A 2017; 121:7059-7069. [PMID: 28853889 DOI: 10.1021/acs.jpca.7b07180] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protonated ions of acetylacetone, H+(Hacac), and their argon-tagged analogues are produced via a pulsed discharge and cooled in a supersonic expansion. These ions are mass analyzed, selected in a time-of-flight spectrometer, and studied with infrared laser photodissociation spectroscopy using the method of rare-gas atom tagging. Computational studies at the DFT/B3LYP level are employed to elucidate the structures and spectra of these ions, which are expected to exist as either enol- or keto-based tautomers. The protonated acetylacetone ion is found to form a single enol-based isomer. Adding one or two water molecules to this ion, for example, H+(Hacac)(H2O)1,2, produces primarily enol-based structures, although a small concentration of keto structures also contribute to the spectra. The vibrational patterns resulting from hydrogen bonding in these systems are not well-described by theory. Addition of a third water molecule to form the H+(Hacac)(H2O)3 ion causes a significant change in the spectroscopy, attributed to proton transfer from the H+(Hacac) ion into the water solvent.
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Affiliation(s)
- Daniel T Mauney
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Jonathon A Maner
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Michael A Duncan
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
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Wagner JP, McDonald DC, Duncan MA. Near-infrared spectroscopy and anharmonic theory of the H2O+Ar1,2 cation complexes. J Chem Phys 2017; 147:104302. [DOI: 10.1063/1.4998419] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- J. Philipp Wagner
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - David C. McDonald
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
| | - Michael A. Duncan
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, Georgia 30602, USA
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15
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McDonald DC, Mauney DT, Leicht D, Marks JH, Tan JA, Kuo JL, Duncan MA. Communication: Trapping a proton in argon: Spectroscopy and theory of the proton-bound argon dimer and its solvation. J Chem Phys 2017; 145:231101. [PMID: 28010076 DOI: 10.1063/1.4972581] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ion-molecule complexes of the form H+Arn are produced in pulsed-discharge supersonic expansions containing hydrogen and argon. These ions are analyzed and mass-selected in a reflectron spectrometer and studied with infrared laser photodissociation spectroscopy. Infrared spectra for the n = 3-7 complexes are characterized by a series of strong bands in the 900-2200 cm-1 region. Computational studies at the MP2/aug-cc-pVTZ level examine the structures, binding energies, and infrared spectra for these systems. The core ion responsible for the infrared bands is the proton-bound argon dimer, Ar-H+-Ar, which is progressively solvated by the excess argon. Anharmonic vibrational theory is able to reproduce the vibrational structure, identifying it as arising from the asymmetric proton stretch in combination with multiple quanta of the symmetric argon stretch. Successive addition of argon shifts the proton vibration to lower frequencies, as the charge is delocalized over more ligands. The Ar-H+-Ar core ion has a first solvation sphere of five argons.
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Affiliation(s)
- D C McDonald
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - D T Mauney
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - D Leicht
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - J H Marks
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
| | - J A Tan
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan 10617, People's Republic of China
| | - J-L Kuo
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan 10617, People's Republic of China
| | - M A Duncan
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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16
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Szalay V. Eckart ro-vibrational Hamiltonians via the gateway Hamilton operator: Theory and practice. J Chem Phys 2017; 146:124107. [DOI: 10.1063/1.4978686] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Mahé J, Bakker DJ, Jaeqx S, Rijs AM, Gaigeot MP. Mapping gas phase dipeptide motions in the far-infrared and terahertz domain. Phys Chem Chem Phys 2017; 19:13778-13787. [DOI: 10.1039/c7cp00369b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Vibrational signatures of Ac-Phe-AA-NH2 dipeptides are recorded and analysed in the far IR/THz spectral domain (100–800 cm−1, 3–24 THz), with the ‘AA’ amino acid chosen within the series ‘AA’ = Gly, Ala, Pro, Cys, Ser, Val. Phe stands for phenylalanine.
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Affiliation(s)
- Jérôme Mahé
- LAMBE CNRS UMR8587
- Université d'Evry val d'Essonne
- 91025 Evry
- France
- Université Paris-Saclay
| | - Daniël J. Bakker
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Sander Jaeqx
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Anouk M. Rijs
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Marie-Pierre Gaigeot
- LAMBE CNRS UMR8587
- Université d'Evry val d'Essonne
- 91025 Evry
- France
- Université Paris-Saclay
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18
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Tennyson J. Perspective: Accurate ro-vibrational calculations on small molecules. J Chem Phys 2016; 145:120901. [DOI: 10.1063/1.4962907] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Jonathan Tennyson
- Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London, United Kingdom
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19
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Sarka J, Császár AG. Interpretation of the vibrational energy level structure of the astructural molecular ion H5+ and all of its deuterated isotopomers. J Chem Phys 2016; 144:154309. [DOI: 10.1063/1.4946808] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- János Sarka
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
| | - Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, P.O. Box 32, H-1518 Budapest 112, Hungary
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20
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Lin Z, McCoy AB. Probing the Relationship Between Large-Amplitude Motions in H5(+) and Proton Exchange Between H3(+) and H2. J Phys Chem A 2015; 119:12109-18. [PMID: 26244451 DOI: 10.1021/acs.jpca.5b05774] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Understanding the spectroscopy and dynamics of H5(+) is central in gaining insights into the H3(+) + H2 → H5(+) → H2 + H3(+) proton transfer reaction. This molecular ion exhibits large-amplitude vibrations, which allow for the transfer of a proton between H3(+) and H2 even in its ground vibrational state. With vibrational excitation, the number of open channels for permutations of protons increase. In this work, the minimized energy path variant of diffusion Monte Carlo is used to investigate how the energetically accessible proton permutations evolve as H5(+) is dissociated into H3(+) + H2. Two mechanisms for proton permutation are investigated. The first is the proton hop, which correlates to large-amplitude vibrations of the central proton in H5(+). The second is the exchange of a pair of hydrogen atoms between H3(+) and H2. This mechanism requires several proton hops along with a 120° rotation of H3(+) within the H5(+) molecular ion. This analysis shows that while there is a narrow region of configuration space over which both isomerization processes are energetically accessible, full permutation of the five protons in H5(+) more likely occurs through a stepwise mechanism. Such full permutation of the protons becomes accessible when the shared proton stretch is excited to the vpt = 2 or 3 excited state. The effects of deuteration and rotational excitation of the H2 and H3(+) products are also investigated. Deuteration inhibits permutation of protons, while rotational excitation has only a small impact on these processes.
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Affiliation(s)
- Zhou Lin
- Department of Chemistry and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
| | - Anne B McCoy
- Department of Chemistry and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
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21
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Hornung B, Harvey JN, Preston TJ, Dunning GT, Orr-Ewing AJ. Empirical Valence Bond Theory Studies of the CH4 + Cl → CH3 + HCl Reaction. J Phys Chem A 2015; 119:9590-8. [DOI: 10.1021/acs.jpca.5b06418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Balázs Hornung
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Jeremy N. Harvey
- Department
of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001, Leuven (Heverlee), Belgium
| | - Thomas J. Preston
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Greg T. Dunning
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
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22
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Marlett ML, Lin Z, McCoy AB. Rotation/Torsion Coupling in H5+, D5+, H4D+, and HD4+ Using Diffusion Monte Carlo. J Phys Chem A 2015. [DOI: 10.1021/acs.jpca.5b05773] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Melanie L. Marlett
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Zhou Lin
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Anne B. McCoy
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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23
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Valdés Á, Prosmiti R. Theoretical predictions on the role of the internal H3(+) rotation in the IR spectra of the H5(+) and D5(+) cations. Phys Chem Chem Phys 2015; 16:6217-24. [PMID: 24562473 DOI: 10.1039/c3cp55301a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The IR spectra of the H5(+) and D5(+) cations in the mid- and far-IR spectral regions have been recently reported by experimentalists. These spectra show very rich vibrational patterns representing a challenge for state-of-the-art theoretical methods to provide definitive interpretations of them. Using a full-dimensional quantum anharmonic treatment, within the MCTDH approach, together with ab initio potential and dipole moment surfaces, the predominant features in the spectra are assigned, completing an important part in previous theoretical and experimental comparisons. The internal rotation of the H3(+) unit by exciting the H3(+)-H2 stretching mode is found to correspond to the new calculated features at 1182, 1876, and 2139 cm(-1) of the H5(+) spectrum, leading to a consistent assignment with the experimental spectra. In the calculated spectra of both H5(+) and D5(+) clusters, the progressions in the H3(+)-H2 stretch of the shared proton and the in- and out-of- plane H3(+) rotation are demonstrated to be the main features. Such states are expected to play a central role in the low temperature hydrogen/deuterium proton hop/exchange H3(+) + H2 reactions.
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Affiliation(s)
- Álvaro Valdés
- Instituto de Física Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain.
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24
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Pettersson J, Andersson P, Hellberg F, Öjekull J, Thomas R, Larsson M. Dissociative recombination and excitation of D5+by collisions with low-energy electrons. Mol Phys 2015. [DOI: 10.1080/00268976.2014.1003985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Sarka J, Fábri C, Szidarovszky T, Császár AG, Lin Z, McCoy AB. Modelling rotations, vibrations, and rovibrational couplings in astructural molecules – a case study based on the H+5 molecular ion. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1020074] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- János Sarka
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Budapest, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, Budapest, Hungary
| | - Csaba Fábri
- Laboratory of Physical Chemistry, ETH Zürich, Zürich, Switzerland
| | - Tamás Szidarovszky
- MTA-ELTE Complex Chemical Systems Research Group, Budapest, Hungary
- Department of Chemistry, School of Science, The University of Tokyo, Tokyo, Japan
| | - Attila G. Császár
- Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, Budapest, Hungary
- MTA-ELTE Complex Chemical Systems Research Group, Budapest, Hungary
| | - Zhou Lin
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Anne B. McCoy
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
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26
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Qu C, Bowman JM. Diffusion Monte Carlo Calculations of Zero-Point Structures of Partially Deuterated Isotopologues of H7+. J Phys Chem B 2014; 118:8221-6. [DOI: 10.1021/jp501371z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Chen Qu
- Department of Chemistry and
Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M. Bowman
- Department of Chemistry and
Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, United States
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27
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Lin Z, McCoy AB. The role of large-amplitude motions in the spectroscopy and dynamics of H5+. J Chem Phys 2014; 140:114305. [DOI: 10.1063/1.4868098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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28
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Valdés Á, Prosmiti R. First-principles simulations of vibrational states and spectra for H5(+) and D5(+) clusters using multiconfiguration time-dependent Hartree approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 119:26-33. [PMID: 23763866 DOI: 10.1016/j.saa.2013.05.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/06/2013] [Accepted: 05/12/2013] [Indexed: 06/02/2023]
Abstract
Simulations of the infrared (IR) spectra of the H5(+) and D5(+) clusters are carried out in the whole energy range, using a recent, reliable "on the fly" DFT-based potential energy surface, and its corresponding dipole moment surface. For the present study we adopted a recently proposed four-dimensional quantum model to describe the proton transfer motion between the two vibrating H2 or D2 units. Time-dependent and time-independent approaches within the multiconfiguration time-dependent Hartree method are employed for investigating the vibrational dynamics of the complexes. The obtained spectra are compared with recent experimental data available for energies up to 4500 and 3500 cm(-1) for the H5(+) and D5(+), respectively. Even though the present results are based on a reduced dimensional model, the infrared spectra are shown to be in good qualitative accord with those observed experimentally. Also as the reported data are subject to the potential energy surface, comparisons with previous theoretical calculations based on an analytical ab initio parameterized surface are also presented. The differences on the topology of the potentials are discussed in connection with their effect on the spectral features. We found that the main characteristics of the experimentally observed spectra are reproduced by both surfaces, evaluating in this way the sensitivity of such computations on the quality of the underlying potential. This finding serves to connect aspects of the potential surface of these systems to their spectral complexity, and could be indicative to calibrate intrinsic errors in their calculation for future studies.
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Affiliation(s)
- Álvaro Valdés
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
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29
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Barragán P, Pérez de Tudela R, Qu C, Prosmiti R, Bowman JM. Full-dimensional quantum calculations of the dissociation energy, zero-point, and 10 K properties of H7+/D7+ clusters using an ab initio potential energy surface. J Chem Phys 2014; 139:024308. [PMID: 23862944 DOI: 10.1063/1.4812557] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Diffusion Monte Carlo (DMC) and path-integral Monte Carlo computations of the vibrational ground state and 10 K equilibrium state properties of the H7 (+)/D7 (+) cations are presented, using an ab initio full-dimensional potential energy surface. The DMC zero-point energies of dissociated fragments H5 (+)(D5 (+))+H2(D2) are also calculated and from these results and the electronic dissociation energy, dissociation energies, D0, of 752 ± 15 and 980 ± 14 cm(-1) are reported for H7 (+) and D7 (+), respectively. Due to the known error in the electronic dissociation energy of the potential surface, these quantities are underestimated by roughly 65 cm(-1). These values are rigorously determined for first time, and compared with previous theoretical estimates from electronic structure calculations using standard harmonic analysis, and available experimental measurements. Probability density distributions are also computed for the ground vibrational and 10 K state of H7 (+) and D7 (+). These are qualitatively described as a central H3 (+)/D3 (+) core surrounded by "solvent" H2/D2 molecules that nearly freely rotate.
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Affiliation(s)
- Patricia Barragán
- Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain
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30
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Qu C, Prosmiti R, Bowman JM. MULTIMODE calculations of the infrared spectra of H 7 + and D 7 + using ab initio potential energy and dipole moment surfaces. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1413-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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31
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Song H, Lee SY, Yang M, Lu Y. Full-dimensional quantum calculations of the vibrational states of H5(+). J Chem Phys 2013; 138:124309. [PMID: 23556725 DOI: 10.1063/1.4797464] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Full-dimensional quantum calculations of the vibrational states of H5(+) have been performed on the accurate potential energy surface developed by Xie et al. [J. Chem. Phys. 122, 224307 (2005)]. The zero point energies of H5(+), H4D(+), D4H(+), and D5(+) and their ground-state geometries are presented and compared with earlier theoretical results. The first 10 low-lying excited states of H5(+) are assigned to the fundamental, overtone, and combination of the H2-H3(+) stretch, the shared proton hopping and the out-of-plane torsion. The ground-state torsional tunneling splitting, the fundamental of the photon hopping mode and the first overtone of the torsion mode are 87.3 cm(-1), 354.4 cm(-1), and 444.0 cm(-1), respectively. All of these values agree well with the diffusion Monte Carlo and multi-configuration time-dependent Hartree results where available.
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Affiliation(s)
- Hongwei Song
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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32
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DeBlase AF, Bloom S, Lectka T, Jordan KD, McCoy AB, Johnson MA. Origin of the diffuse vibrational signature of a cyclic intramolecular proton bond: Anharmonic analysis of protonated 1,8-disubstituted naphthalene ions. J Chem Phys 2013; 139:024301. [DOI: 10.1063/1.4810878] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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33
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Lin Z, McCoy AB. Investigation of the structure and spectroscopy of H5(+) using diffusion Monte Carlo. J Phys Chem A 2013; 117:11725-36. [PMID: 23560453 DOI: 10.1021/jp4014652] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The results of diffusion Monte Carlo (DMC) calculations of the ground and selected excited states of H5(+) and its deuterated analogues are presented. Comparisons are made between the results obtained from two recently reported potential surfaces. Both of these surfaces are based on CCSD(T) electronic energies, but the fits display substantial differences in the energies of low-lying stationary points. Little sensitivity to these features is found in the DMC results, which yield zero-point energies based on the two surfaces that differ by between 20 and 30 cm(–1) for all twelve isotopologues of H5(+). Likewise, projections of the ground state probability amplitudes, evaluated for the two surfaces, are virtually identical. By using the ground state probability amplitudes, vibrationally averaged rotational constants and dipole moments were calculated. On the basis of these calculations, all isotopologues are shown to be near-prolate symmetric tops. Further, in cases where the ion had a nonzero dipole moment, the magnitude of the vibrationally averaged dipole moment was found to range from 0.33 to 1.15 D, which is comparable to the dipole moments of H2D+ and HD2(+). Excited states with up to three quanta in the shared proton stretch and one quantum in the in-phase stretch of the outer H2 groups were also investigated. Trends in the energies and the properties of these states are discussed.
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Affiliation(s)
- Zhou Lin
- Department of Chemistry and Biochemistry, The Ohio State University , Columbus, Ohio 43210, United States
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34
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Valdés Á, Prosmiti R. Theoretical Investigation of the Infrared Spectra of the H5+ and D5+ Cations. J Phys Chem A 2013; 117:9518-24. [DOI: 10.1021/jp3121947] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Álvaro Valdés
- Instituto de Fsica Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain
| | - Rita Prosmiti
- Instituto de Fsica Fundamental (IFF-CSIC), CSIC, Serrano 123, 28006 Madrid, Spain
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35
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Young JW, Cheng TC, Bandyopadhyay B, Duncan MA. IR photodissociation spectroscopy of H7(+), H9(+), and their deuterated analogues. J Phys Chem A 2013; 117:6984-90. [PMID: 23374094 DOI: 10.1021/jp312630x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cluster ions of H7(+)/D7(+) and H9(+)/D9(+) produced in a supersonic molecular beam with a pulsed discharge source are mass selected and studied with infrared laser photodissociation spectroscopy. Photodissociation occurs by the loss of H2 (D2) from each cluster, producing resonances in the 2000-4500 cm(-1) region. Vibrational patterns indicate that these ions consist of an H3(+) (D3(+)) core ion solvated by H2 (D2) molecules. There is no evidence for the shared proton structure seen previously for H5(+). The H3(+) ion core vibrational bands are weakened and broadened significantly, presumably by enhanced rates of intramolecular vibrational relaxation. Computational studies at the DFT/B3LYP or MP2 levels of theory (including scaling) are adequate to reproduce qualitative details of the vibrational spectra, but neither provides quantitative agreement with vibrational frequencies.
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Affiliation(s)
- J W Young
- Department of Chemistry, University of Georgia, Athens, Georgia 30602, USA
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36
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Affiliation(s)
- Zhou Lin
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Anne B McCoy
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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