1
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Jungen C, Pratt ST. An energy-modified quantum defect method for the analysis of Rydberg spectra: Application to 2-butyne. J Chem Phys 2024; 161:094107. [PMID: 39230370 DOI: 10.1063/5.0224294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2024] [Accepted: 08/15/2024] [Indexed: 09/05/2024] Open
Abstract
The high resolution Rydberg absorption spectrum of 2-butyne C4H6 recorded previously at the SOLEIL synchrotron facility has been interpreted using multichannel quantum defect theory (MQDT). The calculations are based on the continuum scattering calculations of Xu et al., J. Chem. Phys. 136, 154303 (2012) and of Jacovella et al., J. Phys. Chem. A 119, 12339 (2015) pertaining to the dipole-allowed excited state symmetries in absorption from the ground state. In contrast to the traditional approach of calculating low-lying electronic states first and then attempting to extend the calculations to ever higher energy, here the analysis proceeds through the extension of these detailed calculations of the electronic continuum scattering down into the discrete region of the spectrum. The continuum reaction matrices and dipole transition moments are adapted to the discrete Rydberg region via the use of an energy-modified formulation of MQDT theory and associated energy dependences of the quantum defects. The analysis reproduces more than 40 Rydberg states from n ≈ 10 down to the 3d and 4s levels with an rms error of better than 20 cm-1. These belong to five Rydberg series with three different molecular symmetries. While the approach predicts many additional series, most of these are calculated and observed to carry only little oscillator strength. The analysis shows that the Rydberg spectrum is dominated by the excitation of an e″ symmetry electron of fδ and gπ type, in line with what previous studies of the above-threshold shape resonance of 2-butyne have shown. The present study is intended to serve as an example showing how first principles continuum calculations may be useful for the interpretation of highly bound discrete states in a range that poses problems for the standard ab initio techniques. The quantitative treatment of the dipole absorption cross sections is deferred to a future paper.
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Affiliation(s)
- Ch Jungen
- Laboratoire Aimé Cotton du CNRS, Bâtiment 505 Université de Paris-Saclay, F-91405 Orsay, France
| | - S T Pratt
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
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2
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Caster KL, Lee J, Donnellan Z, Selby TM, Osborn DL, Goulay F. Formation of a Resonance-Stabilized Radical Intermediate by Hydroxyl Radical Addition to Cyclopentadiene. J Phys Chem A 2022; 126:9031-9041. [DOI: 10.1021/acs.jpca.2c06934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Kacee L. Caster
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - James Lee
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - Zachery Donnellan
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - Talitha M. Selby
- Department of Mathematics and Natural Sciences, University of Wisconsin-Milwaukee, West Bend, Wisconsin53095, United States
| | - David L. Osborn
- Combustion Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California94551, United States
- Department of Chemical Engineering, University of California, Davis, Davis, California95616, United States
| | - Fabien Goulay
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
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3
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Huang J, Huang C, Wu X, Hou Q, Tian G, Yang J, Zhang F. Combined experimental and theoretical study on photoionization cross sections of benzonitrile and o/m/p-cyanotoluene. J Chem Phys 2021; 154:244301. [PMID: 34241365 DOI: 10.1063/5.0053119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Photoionization cross sections (PICSs) for the products of the reaction from CN with toluene, including benzonitrile and o/m/p-cyanotoluene, were obtained at photon energies ranging from ionization thresholds to 14 eV by tunable synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). Theoretical calculations based on the frozen-core Hartree-Fock approximation and Franck-Condon simulations were carried out to cross-verify the measured PICS. The results show that the photoionization cross sections of benzonitrile and cyanotoluene isomers are similar. The generalized charge decomposition analysis was used to investigate the components of the highest occupied molecular orbital (HOMO) and HOMO-1. It was found that the HOMO and HOMO-1 of benzonitrile and cyanotoluene isomers are dominated by the features of the benzene ring, indicating that the substitution of CN and methyl has a minor influence on the PICS of the studied molecules. The reported PICS on benzonitrile and cyanotoluene isomers in the present work could contribute to the near-threshold PIMS experiments and determine the ionization and dissociation rates in interstellar space for these crucial species. The theoretical analysis on characteristics of molecular orbitals provides clues to estimating the PICS of similar substituted aromatic compounds.
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Affiliation(s)
- Jiabin Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Can Huang
- Chair of Technical Thermodynamics, RWTH Aachen University, 52062 Aachen, Germany
| | - Xiaoqing Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Qifeng Hou
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Guangjun Tian
- Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004, People's Republic of China
| | - Jiuzhong Yang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Feng Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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4
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Rousso AC, Jasper AW, Ju Y, Hansen N. Extreme Low-Temperature Combustion Chemistry: Ozone-Initiated Oxidation of Methyl Hexanoate. J Phys Chem A 2020; 124:9897-9914. [PMID: 33174431 DOI: 10.1021/acs.jpca.0c07584] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The accelerating chemical effect of ozone addition on the oxidation chemistry of methyl hexanoate [CH3(CH2)4C(═O)OCH3] was investigated over a temperature range from 460 to 940 K. Using an externally heated jet-stirred reactor at p = 700 Torr (residence time τ = 1.3 s, stoichiometry φ = 0.5, 80% argon dilution), we explored the relevant chemical pathways by employing molecular-beam mass spectrometry with electron and single-photon ionization to trace the temperature dependencies of key intermediates, including many hydroperoxides. In the absence of ozone, reactivity is observed in the so-called low-temperature chemistry (LTC) regime between 550 and 700 K, which is governed by hydroperoxides formed from sequential O2 addition and isomerization reactions. At temperatures above 700 K, we observed the negative temperature coefficient (NTC) regime, in which the reactivity decreases with increasing temperatures, until near 800 K, where the reactivity increases again. Upon addition of ozone (1000 ppm), the overall reactivity of the system is dramatically changed due to the time scale of ozone decomposition in comparison to fuel oxidation time scales of the mixtures at different temperatures. While the LTC regime seems to be only slightly affected by the addition of ozone with respect to the identity and quantity of the observed intermediates, we observed an increased reactivity in the intermediate NTC temperature range. Furthermore, we observed experimental evidence for an additional oxidation regime in the range near 500 K, herein referred to as the extreme low-temperature chemistry (ELTC) regime. Experimental evidence and theoretical rate constant calculations indicate that this ELTC regime is likely to be initiated by H abstraction from methyl hexanoate via O atoms, which originate from thermal O3 decomposition. The theoretical calculations show that the rate constants for methyl ester initiation via abstraction by O atoms increase dramatically with the size of the methyl ester, suggesting that ELTC is likely not important for the smaller methyl esters. Experimental evidence is provided indicating that, similar to the LTC regime, the chemistry in the ELTC regime is dominated by hydroperoxide chemistry. However, mass spectra recorded at various reactor temperatures and at different photon energies provide experimental evidence of some differences in chemical species between the ELTC and the LTC temperature ranges.
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Affiliation(s)
- Aric C Rousso
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ahren W Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Yiguang Ju
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Nils Hansen
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, United States
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5
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Fan JN, Cui TT, Qin ZB, Zheng XF, Cui ZF. Experimental and theoretical study on p-chlorofluorobenzene in the S0, S1 and D0 states. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp2001005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Jia-nan Fan
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu 241000, China
| | - Ting-ting Cui
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu 241000, China
| | - Zheng-bo Qin
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu 241000, China
| | - Xian-feng Zheng
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu 241000, China
| | - Zhi-feng Cui
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu 241000, China
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Hrodmarsson HR, Loison JC, Jacovella U, Holland DMP, Boyé-Péronne S, Gans B, Garcia GA, Nahon L, Pratt ST. Valence-Shell Photoionization of C4H5: The 2-Butyn-1-yl Radical. J Phys Chem A 2019; 123:1521-1528. [DOI: 10.1021/acs.jpca.8b11809] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- H. R. Hrodmarsson
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - J.-C. Loison
- Institut des Sciences Moléculaires, Université Bordeaux, 33400 Talence, France
| | - U. Jacovella
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - D. M. P. Holland
- STFC, Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD, United Kingdom
| | - S. Boyé-Péronne
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS & Univ. Paris-Sud & Université Paris-Saclay, F-91405 Orsay, France
| | - B. Gans
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS & Univ. Paris-Sud & Université Paris-Saclay, F-91405 Orsay, France
| | - G. A. Garcia
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - L. Nahon
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - S. T. Pratt
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439 United States
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7
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Sen A, Pratt ST. Double-resonance studies of electronically autoionizing states of molecular nitrogen. Mol Phys 2019. [DOI: 10.1080/00268976.2018.1544672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Ananya Sen
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL, USA
| | - S. T. Pratt
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, IL, USA
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8
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Sen A, Pratt ST, Reid KL. Circular dichroism in photoelectron images from aligned nitric oxide molecules. J Chem Phys 2017; 147:013927. [DOI: 10.1063/1.4982218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ananya Sen
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - S. T. Pratt
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - K. L. Reid
- School of Chemistry, University of Nottingham, Nottingham NG7 2RD, United Kingdom
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9
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Garcia GA, Dossmann H, Nahon L, Daly S, Powis I. Identifying and Understanding Strong Vibronic Interaction Effects Observed in the Asymmetry of Chiral Molecule Photoelectron Angular Distributions. Chemphyschem 2017; 18:500-512. [PMID: 27973748 DOI: 10.1002/cphc.201601250] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/11/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Gustavo A. Garcia
- Synchrotron SOLEIL, L'Orme des Merisiers; St. Aubin BP 48 91192 Gif sur Yvette France
| | - Héloïse Dossmann
- Synchrotron SOLEIL, L'Orme des Merisiers; St. Aubin BP 48 91192 Gif sur Yvette France
- Current address: Sorbonne Universités; UPMC Univ Paris 06, CNRS, Institut Parisien de Chimie Moléculaire (IPCM); 4 Place Jussieu 75252 Paris Cedex 05 France
| | - Laurent Nahon
- Synchrotron SOLEIL, L'Orme des Merisiers; St. Aubin BP 48 91192 Gif sur Yvette France
| | - Steven Daly
- School of Chemistry; University of Nottingham; Nottingham NG7 2RD UK
- Current address: Institut Lumiere Matière, UMR5306, CNRS; Université Lyon 1; 69622 Villeurbanne France
| | - Ivan Powis
- School of Chemistry; University of Nottingham; Nottingham NG7 2RD UK
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10
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Jacovella U, Holland DMP, Boyé-Péronne S, Gans B, de Oliveira N, Ito K, Joyeux D, Archer LE, Lucchese RR, Xu H, Pratt ST. A Near-Threshold Shape Resonance in the Valence-Shell Photoabsorption of Linear Alkynes. J Phys Chem A 2015; 119:12339-48. [DOI: 10.1021/acs.jpca.5b06949] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- U. Jacovella
- Laboratorium
für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - D. M. P. Holland
- STFC, Daresbury
Laboratory, Daresbury, Warrington, Cheshire WA4 4AD, U.K
| | - S. Boyé-Péronne
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS & Univ. Paris-Sud, F-91405 Orsay, France
| | - Bérenger Gans
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS & Univ. Paris-Sud, F-91405 Orsay, France
| | - N. de Oliveira
- Synchrotron Soleil,
L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - K. Ito
- Synchrotron Soleil,
L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - D. Joyeux
- Synchrotron Soleil,
L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - L. E. Archer
- Synchrotron Soleil,
L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - R. R. Lucchese
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Hong Xu
- Argonne National
Laboratory, Argonne, Illinois 60439, United States
| | - S. T. Pratt
- Argonne National
Laboratory, Argonne, Illinois 60439, United States
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11
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Leach S. Size effects on cation heats of formation. IV. Methyl and ethyl substitutions in methyl, methylene, acetylene and ethene. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1031838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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Jacovella U, Holland DMP, Boyé-Péronne S, Gans B, de Oliveira N, Joyeux D, Archer LE, Lucchese RR, Xu H, Pratt ST. High-resolution vacuum-ultraviolet photoabsorption spectra of 1-butyne and 2-butyne. J Chem Phys 2015. [DOI: 10.1063/1.4926541] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- U. Jacovella
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - D. M. P. Holland
- STFC, Daresbury Laboratory, Daresbury, Warrington, Cheshire WA4 4AD, United Kingdom
| | - S. Boyé-Péronne
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS and Université Paris-Sud, F-91405 Orsay, France
| | - B. Gans
- Institut des Sciences Moléculaires d’Orsay, UMR 8214, CNRS and Université Paris-Sud, F-91405 Orsay, France
| | - N. de Oliveira
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - D. Joyeux
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - L. E. Archer
- Synchrotron Soleil, L’Orme des Merisiers, F-91192 Gif-sur-Yvette, France
| | - R. R. Lucchese
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA
| | - H. Xu
- Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - S. T. Pratt
- Argonne National Laboratory, Argonne, Illinois 60439, USA
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13
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Xu H, Pratt ST. Photodissociation of Methyl Iodide via Selected Vibrational Levels of the B̃ ((2)E3/2)6s Rydberg State. J Phys Chem A 2015; 119:7548-58. [PMID: 25946320 DOI: 10.1021/acs.jpca.5b00860] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have determined the I (2)P3/2 and (2)P1/2 branching fractions following the photodissociation of methyl iodide (CH3I) via a number of vibronic bands associated with the B̃ ((2)E3/2)6s Rydberg state at excitation wavelengths between 201.2 and 192.7 nm. Vacuum ultraviolet light at 118.2 nm was used to ionize both the product iodine atoms and the methyl radical cofragments, and velocity map ion imaging was used to determine the product translational energy distributions and angular distributions. The known relative photoionization cross sections for I (2)P3/2 and (2)P1/2 at 118.2 nm were used to determine the corresponding branching fractions. The results extend our earlier work at 193 nm by Xu et al. (J. Chem. Phys. 2013, 139, 214310), and complement the closely related work of González et al. (J. Chem. Phys. 2011, 135, 021102). We find that for most of the excited vibronic levels of the B̃ state studied, the I (2)P3/2 branching ratio is small, but nonzero, and that this channel is associated with internally excited CH3 radicals. The results are discussed in relation to the recent theoretical results of Alekseyev et al. (J. Chem. Phys. 2011, 134, 044303).
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Affiliation(s)
- Hong Xu
- Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - S T Pratt
- Argonne National Laboratory, Argonne, Illinois 60439, United States
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14
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Jacovella U, Gans B, Merkt F. Internal rotation, spin–orbit coupling, and low-frequency vibrations in the ground state of CH3–CC–CH+3and CD3–CC–CD+3. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1005708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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15
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Capron M, Bourgalais J, Abhinavam Kailasanathan RK, Osborn DL, Le Picard SD, Goulay F. Flow tube studies of the C(3P) reactions with ethylene and propylene. Phys Chem Chem Phys 2015; 17:23833-46. [DOI: 10.1039/c5cp03918e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Product detection studies of C(3P) atom reactions with ethylene, C2H4(X1Ag) and propylene, C3H6(X1A′) are carried out in a flow tube reactor at 332 K and 4 Torr (553.3 Pa) under multiple collision conditions.
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Affiliation(s)
- Michael Capron
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | - Jérémy Bourgalais
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | | | - David L. Osborn
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
| | - Sébastien D. Le Picard
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | - Fabien Goulay
- Department of Chemistry
- West Virginia University
- Morgantown
- USA
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16
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Powis I. Communication: The influence of vibrational parity in chiral photoionization dynamics. J Chem Phys 2014; 140:111103. [DOI: 10.1063/1.4869204] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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17
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Xu H, Pratt ST. A new look at the photodissociation of methyl iodide at 193 nm. J Chem Phys 2013; 139:214310. [DOI: 10.1063/1.4829747] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Goulay F, Derakhshan A, Maher E, Trevitt AJ, Savee JD, Scheer AM, Osborn DL, Taatjes CA. Formation of dimethylketene and methacrolein by reaction of the CH radical with acetone. Phys Chem Chem Phys 2013; 15:4049-58. [PMID: 23403615 DOI: 10.1039/c3cp43829e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of the methylidyne radical (CH) with acetone ((CH(3))(2)C[double bond, length as m-dash]O) is studied at room temperature and at a pressure of 4 Torr (533.3 Pa) using a multiplexed photoionization mass spectrometer coupled to the tunable vacuum ultraviolet synchrotron radiation of the Advanced Light Source at Lawrence Berkeley National Laboratory. The CH radicals are generated by 248 nm multiphoton photolysis of bromoform and react with acetone in an excess of helium and nitrogen gas flow. The main observed reaction exit channel is elimination of a hydrogen atom to form C(4)H(6)O isomers. Analysis of photoionization spectra identifies dimethylketene and methacrolein as the only H-elimination products. The best fit to the data gives branching ratios of 0.68 ± 0.14 for methacrolein and 0.32 ± 0.07 for dimethylketene. A methylketene spectrum measured here is used to reanalyze the photoionization spectrum obtained at m/z = 56 for the CH + acetaldehyde reaction, (Goulay et al., J. Phys. Chem. A, 2012, 116, 6091) yielding new H-loss branching ratios of 0.61 ± 0.12 for acrolein and 0.39 ± 0.08 for methylketene. The contribution from methyleneoxirane to the reaction product distribution is revised to be negligible. Coupled with additional product detection for the CD + acetone reaction, these observations pave the way for development of general set of reaction mechanisms for the addition of CH to compounds containing an acetyl subgroup.
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Affiliation(s)
- Fabien Goulay
- Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, USA.
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19
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Staniforth M, Daly S, Reid KL, Powis I. A generic π* shape resonance observed in energy-dependent photoelectron angular distributions from two-colour, resonant multiphoton ionization of difluorobenzene isomers. J Chem Phys 2013; 139:064304. [DOI: 10.1063/1.4817324] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Xu H, Pratt ST. Photodissociation of Anisole and Absolute Photoionization Cross-Section of the Phenoxy Radical. J Phys Chem A 2013; 117:12075-81. [DOI: 10.1021/jp4047177] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hong Xu
- Argonne National Laboratory,
Argonne, Illinois 60439, United States
| | - S. T. Pratt
- Argonne National Laboratory,
Argonne, Illinois 60439, United States
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21
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Trevitt AJ, Prendergast MB, Goulay F, Savee JD, Osborn DL, Taatjes CA, Leone SR. Product Branching Fractions of the CH + Propene Reaction from Synchrotron Photoionization Mass Spectrometry. J Phys Chem A 2013; 117:6450-7. [DOI: 10.1021/jp404965k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Adam J. Trevitt
- School of
Chemistry, University of Wollongong, NSW
2522 Australia
| | | | - Fabien Goulay
- Department
of Chemistry, West Virginia University,
Morgantown, West Virginia
26506, United States
| | - John D. Savee
- Combustion
Research Facility,
Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - David L. Osborn
- Combustion
Research Facility,
Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - Craig A. Taatjes
- Combustion
Research Facility,
Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - Stephen R. Leone
- Departments of Chemistry and Physics,
and Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, United States
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22
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Xu H, Pratt ST. Photoionization Cross Section of the Propargyl Radical and Some General Ideas for Estimating Radical Cross Sections. J Phys Chem A 2012. [DOI: 10.1021/jp309874q] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hong Xu
- Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - S. T. Pratt
- Argonne National Laboratory, Argonne, Illinois 60439, United States
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