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Anstöter CS, West CW, Bull JN, Verlet JRR. The Vitamin E Radical Probed by Anion Photoelectron Imaging. J Phys Chem B 2016; 120:7108-13. [DOI: 10.1021/acs.jpcb.6b05271] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Cate S. Anstöter
- Department
of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | | | - James N. Bull
- Department
of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R. R. Verlet
- Department
of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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2
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Kim H, Park YC, Lee YS. Spin-orbit Effects on the Structure of Haloiodomethane Cations CH2XI+(X=F, Cl, Br, and I). B KOREAN CHEM SOC 2014. [DOI: 10.5012/bkcs.2014.35.3.775] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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3
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Halbert S, Bouchoux G. Isomerization and Dissociation of n-Butylbenzene Radical Cation. J Phys Chem A 2012; 116:1307-15. [DOI: 10.1021/jp211673f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stéphanie Halbert
- Laboratoire des Mécanismes
Réactionnels,
Ecole Polytechnique, CNRS, 91128 Palaiseau,
France
| | - Guy Bouchoux
- Laboratoire des Mécanismes
Réactionnels,
Ecole Polytechnique, CNRS, 91128 Palaiseau,
France
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4
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Halbert S, Clavaguéra C, Bouchoux G. The shape of gaseousn-butylbenzene: Assessment of computational methods and comparison with experiments. J Comput Chem 2011; 32:1550-60. [DOI: 10.1002/jcc.21733] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 11/10/2010] [Accepted: 11/11/2010] [Indexed: 12/15/2022]
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5
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Tong X, Cerný J, Müller-Dethlefs K, Dessent CEH. Effect of noncovalent interactions on conformers of the n-butylbenzene monomer studied by mass analyzed threshold ionization spectroscopy and basis-set convergent ab initio computations. J Phys Chem A 2008; 112:5866-71. [PMID: 18533642 DOI: 10.1021/jp710997q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Two conformational isomers of the aromatic hydrocarbon n-butylbenzene have been studied using two-color MATI (mass analyzed threshold ionization) spectroscopy to explore the effect of conformation on ionization dynamics. Cationic states of g auche-conformer III and anti- conformers IV were selectively produced by two-color excitation via the respective S 1 origins. Adiabatic ionization potentials of the gauche- and anti-conformations were determined to be 70146 and 69872 +/- 5 cm (-1) respectively. Spectral features and vibrational modes are interpreted with the aid of MP2/cc-pVDZ ab initio calculations, and ionization-induced changes in the molecular conformations are discussed. Complete basis set (CBS) ab initio studies at MP2 level reveal reliable energetics for all four n-butylbenzene conformers observed in earlier two-color REMPI (resonance enhanced multiphoton ionization) spectra. For the S 0 state, the energies of conformer III, IV and V are above conformer I by 130, 289, 73 cm (-1), respectively. Furthermore, the combination of the CBS calculations with the measured REMPI, MATI spectra allowed the determination of the energetics of all four conformers in the S 1 and D 0 states.
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Affiliation(s)
- Xin Tong
- The Photon Science Institute, Alan Turing Building, the School of Chemistry, The University of Manchester, Manchester, M13 9PL, UK
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Tong X, Černý J, Müller-Dethlefs K. Effect of Noncovalent Interactions on the n-Butylbenzene···Ar Cluster Studied by Mass Analyzed Threshold Ionization Spectroscopy and ab initio Computations. J Phys Chem A 2008; 112:5872-7. [DOI: 10.1021/jp710998m] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Xin Tong
- The Photon Science Institute, Alan Turing Building, the School of Chemistry, and the School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, U.K
| | - Jiří Černý
- The Photon Science Institute, Alan Turing Building, the School of Chemistry, and the School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, U.K
| | - Klaus Müller-Dethlefs
- The Photon Science Institute, Alan Turing Building, the School of Chemistry, and the School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, U.K
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7
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Bae YJ, Kim MS. Rotational state selection of a CH3I+ ion beam using vacuum ultraviolet-mass-analyzed threshold ionization spectroscopy: characterization using photodissociation spectroscopy. J Chem Phys 2008; 128:124324. [PMID: 18376936 DOI: 10.1063/1.2884340] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The A(2)A(1)<--X(2)E(3/2) transition of CH(3)I(+) was investigated by photodissociation (PD) of the cation generated by one-photon mass-analyzed threshold ionization (MATI). Compared to the PD spectrum obtained by excitation of the cation in the main 0-0 band in the MATI spectrum, those obtained by excitation of the cations in the satellite structures showed substantially simplified rotational structures for nondegenerate vibronic bands. Spectral simplification occurred because each satellite consisted mostly of cations with one K quantum number. Spectroscopic constants in the ground vibronic state and in the 2(1)3(5), 2(1)3(8), 3(9), and 3(13) nondegenerate vibrational states in A(2)A(1) were determined via spectral fitting. Also, those in the 2(1)3(n)6(1) (n=1?) degenerate state, which had been reported previously, was improved. The K quantum number in each satellite determined by the present high resolution study was compatible with the prediction by the symmetry selection rule for photoionization. That is, the K quantum number of the ion core in high Rydberg states accessed by one-photon excitation was found to be conserved upon pulsed field ionization. This work demonstrates generation of mass-selected, vibronically selected, and K-selected ion beam by one-photon MATI.
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Affiliation(s)
- Yong Jin Bae
- Department of Chemistry, Seoul National University, Seoul 151-742, South Korea
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8
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Lee M, Bae YJ, Kim MS. K selection in one-photon mass-analyzed threshold ionization of CH3I and CD3I to the X2E3/2 state cations. J Chem Phys 2008; 128:044310. [PMID: 18247952 DOI: 10.1063/1.2823032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
One-photon mass-analyzed threshold ionization (MATI) spectra for the X (2)E(3/2) states of CH(3)I(+) and CD(3)I(+) were measured using vacuum ultraviolet radiation generated by four-wave mixing in Kr. Spin-orbit density functional theory calculations at the B3LYP/aug-cc-pVTZ level and spin-orbit/Jahn-Teller calculations were made to aid vibrational assignment. Each vibrational band consisted of several peaks due to different DeltaK transitions, which could be assigned by using molecular parameters determined in the previous high resolution photodissociation spectroscopic study. Possibility of generating mass-selected, vibronically selected and K-selected ion beam with decent intensity by one-photon MATI was demonstrated. The ionization energies to the X (2)E(3/2) states of CH(3)I(+) and CD(3)I(+) corrected for the rotational contribution were 9.5386+/-0.0006 and 9.5415+/-0.0006 eV, respectively.
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Affiliation(s)
- Mina Lee
- Department of Chemistry, Seoul National University, Seoul 151-742, Korea
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Lehrer F, Weinkauf R, Metsala A. Comparison of Photoelectron-Spectroscopy Results to Ab-Initio and Density Functional Calculations: The Ethylbenzene Cation. Z PHYS CHEM 2007. [DOI: 10.1524/zpch.2007.221.5.723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In this work resonant S
0–S
1 two-photon ionization (R2PI) and high-resolution R(1+1’)PI photoelectron spectroscopy (PES) as well as ab initio and density functional (DFT) calculations of ethylbenzene (EB) are combined. Conformer energies and equilibrium geometries have been calculated for neutral and cationic EB with the HF, UHF, B3LYP and the MP2 methods and different basis sets. In agreement with previous results the tail-to-chromophore orientation of neutral EB is orthogonal. This conformer is also the most stable structure in the cation, but a second local minimum in which all carbons lie in a plane (termed “planar” conformer) lays 325cm-1 higher in energy. R(1+1’)PI PE spectra were recorded by time-of-flight spectrometer with an energy resolution (Δ E) below 8 cm-1 and an absolute accuracy of ± 10 cm-1 for electron energies below 200 meV. Because the experiment starts in the orthogonal conformer and ionization is vertical, the recorded PE spectra show the cation ground state vibrations of this conformer. Beside benzene modes also low-energetic tail-to-chromophore modes are observed and assigned by DFT vibrational mode analysis. The differences of the calculated vibrational frequencies between the two conformers are comparable to the deviation between experiment and theory and a conformer assignment by comparison of theory and experiment would be difficult. R(1+1’)PI PE spectra recorded via selected S
1 vibrations provide vibrational assignments for S
1, qualitative S
1–D
0 geometry changes, vibrational symmetries as well as internal vibrational redistribution dynamics in S
1. Charge and spin densities of the neutral and cation were calculated to elucidate the problem of charge delocalization and electronic tail-to-chromophore coupling.
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Bae YJ, Lee M, Kim MS. One-Photon Mass-Analyzed Threshold Ionization Spectroscopy (MATI) of trans-Dichloroethylene (trans-C2H2Cl2): Cation Structure Determination via Franck−Condon Fit. J Phys Chem A 2006; 110:8535-41. [PMID: 16821838 DOI: 10.1021/jp056347b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
One-photon mass-analyzed threshold ionization (MATI) spectrum of trans-C(2)H(2)Cl(2) was obtained by using vacuum ultraviolet radiation generated by four-wave mixing in Kr. The ionization energy determined from the position of the 0-0 band in the spectrum was 9.6306 +/- 0.0006 eV. Ten vibrational fundamentals for the cation were identified. The spectrum also displayed abundant overtones and combinations, most of which could be assigned adequately by comparing with the quantum chemical results. It was found that channel interaction was not important for this system. The equilibrium geometry of the cation was estimated through the Franck-Condon fit.
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Affiliation(s)
- Yong Jin Bae
- National Creative Research Initiative Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University, Seoul 151-742, Korea
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11
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Hobza P, Zahradník R, Müller-Dethlefs K. The World of Non-Covalent Interactions: 2006. ACTA ACUST UNITED AC 2006. [DOI: 10.1135/cccc20060443] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The review focusses on the fundamental importance of non-covalent interactions in nature by illustrating specific examples from chemistry, physics and the biosciences. Laser spectroscopic methods and both ab initio and molecular modelling procedures used for the study of non-covalent interactions in molecular clusters are briefly outlined. The role of structure and geometry, stabilization energy, potential and free energy surfaces for molecular clusters is extensively discussed in the light of the most advanced ab initio computational results for the CCSD(T) method, extrapolated to the CBS limit. The most important types of non-covalent complexes are classified and several small and medium size non-covalent systems, including H-bonded and improper H-bonded complexes, nucleic acid base pairs, and peptides and proteins are discussed with some detail. Finally, we evaluate the interpretation of experimental results in comparison with state of the art theoretical models: this is illustrated for phenol...Ar, the benzene dimer and nucleic acid base pairs. A review with 270 references.
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Lee M, Kim MS. Mass-analyzed threshold ionization study of vinyl bromide cation in the first excited electronic state using vacuum-ultraviolet radiation generated by four-wave mixing in Hg. J Chem Phys 2005; 123:174310. [PMID: 16375531 DOI: 10.1063/1.2104530] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vibrational spectrum of the vinyl bromide cation in the first excited electronic state A 2A' was obtained by one-photon mass-analyzed threshold ionization (MATI) spectroscopy. The use of an improved vacuum-ultraviolet radiation source based on four-wave sum frequency mixing in Hg resulted in excellent sensitivity for MATI signals. From the MATI spectrum, the ionization energy to the A 2A' state of the cation was determined to be 10.9150+/-0.0006 eV. Nearly complete vibrational assignments for the MATI peaks were possible by utilizing the vibrational frequencies and Franck-Condon factors calculated at the density-functional theory (DFT) and time-dependent DFT/B3LYP levels with the 6-311+G(df,p) basis set.
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Affiliation(s)
- Mina Lee
- National Creative Research Initiative Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University, Seoul 151-742, Korea
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Bae YJ, Lee M, Kim MS. One-photon mass-analyzed threshold ionization spectroscopy of 2-chloropropene (2-C3H5Cl) and its vibrational assignment based on the density-functional theory calculations. J Chem Phys 2005; 123:044306. [PMID: 16095357 DOI: 10.1063/1.1988310] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A high-quality mass-analyzed threshold ionization (MATI) spectrum of 2-chloropropene, 2-C3H5Cl, is reported. Its ionization energy determined for the first time from the 0-0 band position was 9.5395+/-0.0006 eV. Almost all the peaks in the MATI spectrum could be vibrationally assigned utilizing the frequencies calculated at the B3LYP6-311++G(3df,3pd) level and the Franck-Condon factors calculated with the molecular parameters obtained at the same level. In particular, the observed methyl torsional progression could be reproduced very well through quantum-mechanical calculations using the molecular parameters obtained at this level. Dramatic lowering of the torsional barrier inferred from the experimental data was entirely compatible with the B3LYP6-311++G(3df,3pd) results. The torsional barrier and the internal rotational constant determined by fits to six torsional peaks were 53.6 and 5.20 cm(-1), respectively. A brief discussion at the level of molecular orbital is presented to account for the dramatic lowering of the torsional barrier upon ionization.
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Affiliation(s)
- Yong Jin Bae
- National Creative Research Initiative Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University, Seoul 151-742, Korea
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Lee M, Kim H, Lee YS, Kim MS. One-photon mass-analyzed threshold ionization spectroscopy of CH2BrI: Extensive bending progression, reduced steric effect, and spin-orbit effect in the cation. J Chem Phys 2005; 123:24310. [PMID: 16050748 DOI: 10.1063/1.1954770] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
One-photon mass-analyzed threshold ionization (MATI) spectrum of CH2BrI was obtained using coherent vacuum-ultraviolet radiation generated by four-wave difference-frequency mixing in Kr. Unlike CH2ClI investigated previously, a very extensive bending (Br-C-I) progression was observed. Vibrational frequencies of CH2BrI+ were measured from the spectra and the vibrational assignments were made by utilizing frequencies calculated by the density-functional-theory (DFT) method using relativistic effective core potentials with and without the spin-orbit terms. A noticeable spin-orbit effect on the vibrational frequencies was observed from the DFT calculations, even though its influence was not so dramatic as in CH2ClI+. A simple explanation based on the bonding characteristics of the molecular orbitals involved in the ionization is presented to account for the above differences between the MATI spectra of CH2BrI and CH2ClI. The 0-0 band of the CH2BrI spectrum could be identified through the use of combined data from calculations and experiments. The adiabatic ionization energy determined from the position of this band was 9.5944+/-0.0006 eV, which was significantly smaller than the vertical ionization energy reported previously.
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Affiliation(s)
- Mina Lee
- National Creative Research Initiative Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University, Seoul 151-742, Korea
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Wang P, Xing X, Lau KC, Woo HK, Ng CY. Rovibrational-state-selected pulsed field ionization-photoelectron study of methyl iodide using two-color infrared-vacuum ultraviolet lasers. J Chem Phys 2004; 121:7049-52. [PMID: 15473769 DOI: 10.1063/1.1807818] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The preparation of methyl iodide (CH(3)I) in selected rovibrational states [nu(7)=1 (C-H stretch); J] by infrared (IR) excitation prior to vacuum ultraviolet (VUV) photoionization has greatly simplified the observed pulsed field ionization-photoelectron (PFI-PE) spectra, allowing the direct determination of the rotational constants B(+)(C(+))=0.254+/-0.003 cm(-1) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)) and the ionization energy (76 896.9+/-0.2 cm(-1)) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)=1,J(+)=3/2)<--CH(3)I(X (1)A(1);nu(7)=1,J=0). The IR-VUV-PFI-PE and IR-VUV-photoion measurements also provide relative state-to-state (nu(7) (+)=1, J(+)<--nu(7)=1, J) cross sections for the photoionization process.
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Affiliation(s)
- P Wang
- Department of Chemistry, University of California at Davis, Davis, California 95616, USA
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Ford MS, Müller-Dethlefs K. The S1neutral and D0cationic states of fluorobenzene and fluorobenzene–argon probed by ZEKE spectroscopy with partial rotational resolution. Phys Chem Chem Phys 2004. [DOI: 10.1039/b312115a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Tong X, Ford MS, Dessent CEH, Müller-Dethlefs K. The effect of conformation on the ionization energetics of n-butylbenzene. I. A threshold ionization study. J Chem Phys 2003. [DOI: 10.1063/1.1626622] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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