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Wang P, Lin Q, Xiao C, Yang X, Liu K, Pan H. Unraveling the Photodissociation Branching and Pathways of Methane at 118 nm by Imaging the CH 3, CH 2, and CH Fragments. J Phys Chem A 2024; 128:5273-5284. [PMID: 38946501 DOI: 10.1021/acs.jpca.4c01914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Under irradiation of a vacuum ultraviolet (VUV) photon, methane dissociates and yields multiple fragments. This photochemical behavior is not only of fundamental importance but also with wide-ranging implications in several branches of science. Despite that and numerous previous investigations, the product channel branching is still under debate, and the underlying dissociation mechanisms remain elusive. In this study, the photofragment imaging technique was exploited for the first time to map out the momentum and anisotropy parameter distributions of the CH3, CH2, and CH fragments at the 118 nm photolysis wavelength (10.48 eV photon energy). In conjunction with previously reported results of the H atom fragment at 121.6 nm (10.2 eV), a complete set of product channel branching in both two-body and three-body fragmentations is accurately determined. We concluded that extensive nonadiabatic transitions partake in the processes with two-body fragmentations accounting for more than 90% of overall photodissociation, for which the channel branching values for CH2 + H2 and CH3 + H are about 0.66 and 0.25, respectively. Careful kinematic analysis enables us to untangle the intertwined triple fragmentations into the CH2(X̃ 3B1 and ã 1A1) + H + H and CH(X2Π) + H + H2 channels and to evidence their underlying sequential (or stepwise) mechanisms. With the aid of electronic correlation and prior theoretical calculations of the potential energy surfaces, the most probable or dominant dissociation pathways are elucidated. Comparisons with fragmentary reports in the literature on various photochemical aspects are also documented, and discrepancies are clarified. This comprehensive study benchmarks the VUV photochemistry of methane and advances our understanding of this important process.
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Affiliation(s)
- Pengcheng Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Qiaosong Lin
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chunlei Xiao
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, P. R. China
| | - Kopin Liu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
- Aerosol Science Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
- Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica, Taipei 10617, Taiwan
| | - Huilin Pan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, CAS, Dalian 116023, P. R. China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, P. R. China
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2
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Egorov O, Rey M, Nikitin AV, Viglaska D. New Theoretical Infrared Line List for the Methyl Radical with Accurate Vibrational Band Origins from High-Level Ab Initio Calculations. J Phys Chem A 2022; 126:6429-6442. [PMID: 36073030 DOI: 10.1021/acs.jpca.2c04822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present work, high-level ab initio calculations were carried out for the ground electronic state of the methyl radical (CH3). Dunning's augmented correlation-consistent orbital basis sets were employed up to the quintuple-ζ valence quality with the core-valence electron correlation [aug-cc-pCV5Z] combined with the single- and double-excitation unrestricted coupled-cluster approach with a perturbative treatment of triple excitations [RHF-UCCSD(T)]. The explicitly correlated version of the coupled-cluster approach [RHF-UCCSD(T)-F12x{x = a, b}] was additionally applied with the core-valence cc-pCVQZ-F12 basis set in order to study convergence with respect to the basis set size. The contributions beyond the coupled-cluster level of the theory like Douglas-Kroll-Hess scalar relativistic Hamiltonian, diabatic Born-Oppenheimer corrections, and high-order electronic correlations have been included into the ab initio potential energy surfaces (PESs). It is shown that the theoretical band origins of CH3 converge gradually to the experimental values when applying the ab initio PESs using the aug-cc-pCVXZ [X = T, Q, and 5] basis sets. For the first time, all available experimental band origins of the gaseous CH3 are reproduced within an accuracy of 0.2 cm-1 using a newly developed PES extrapolated to the complete basis set limit [CBS(TQ5Z)]. The reached accuracy is one order of magnitude better than that of the best available calculations. A new theoretical infrared line list was generated for astrophysical applications using an ab initio dipole moment surface computed at the RHF-UCCSD(T)/aug-cc-pCVQZ level of the theory. The manifestation of a large-amplitude motion in CH3 is also discussed.
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Affiliation(s)
- Oleg Egorov
- Laboratory of Theoretical Spectroscopy, V.E. Zuev Institute of Atmospheric Optics SB RAS 1, Akademician Zuev Sq., Tomsk 634055 Russia
| | - Michaël Rey
- Groupe de Spectrométrie Moléculaire et Atmosphérique UMR CNRS 7331, UFR Sciences BP 1039, 51687 Reims Cedex 2, France
| | - Andrei V Nikitin
- Laboratory of Theoretical Spectroscopy, V.E. Zuev Institute of Atmospheric Optics SB RAS 1, Akademician Zuev Sq., Tomsk 634055 Russia
| | - Dominika Viglaska
- Groupe de Spectrométrie Moléculaire et Atmosphérique UMR CNRS 7331, UFR Sciences BP 1039, 51687 Reims Cedex 2, France
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3
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Cederbaum LS. Fragmentation of Molecules by Virtual Photons from Remote Neighbors. J Phys Chem Lett 2020; 11:8964-8969. [PMID: 33031701 DOI: 10.1021/acs.jpclett.0c02259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
It is shown that a molecule can dissociate by the energy transferred from a remote neighbor. This neighbor can be an excited neutral or ionic atom or molecule. If it is an atom, then the transferred energy is, of course, electronic, and in the case of molecules, it can also be vibrational. Explicit examples are given which demonstrate that the transfer can be highly efficient at distances where there is no bonding between the transmitter and the dissociating molecule.
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Affiliation(s)
- Lorenz S Cederbaum
- Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, Heidelberg D-69120, Germany
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4
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Doddipatla S, He C, Kaiser RI, Luo Y, Sun R, Galimova GR, Mebel AM, Millar TJ. A chemical dynamics study on the gas phase formation of thioformaldehyde (H 2CS) and its thiohydroxycarbene isomer (HCSH). Proc Natl Acad Sci U S A 2020; 117:22712-22719. [PMID: 32859759 PMCID: PMC7502777 DOI: 10.1073/pnas.2004881117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Complex organosulfur molecules are ubiquitous in interstellar molecular clouds, but their fundamental formation mechanisms have remained largely elusive. These processes are of critical importance in initiating a series of elementary chemical reactions, leading eventually to organosulfur molecules-among them potential precursors to iron-sulfide grains and to astrobiologically important molecules, such as the amino acid cysteine. Here, we reveal through laboratory experiments, electronic-structure theory, quasi-classical trajectory studies, and astrochemical modeling that the organosulfur chemistry can be initiated in star-forming regions via the elementary gas-phase reaction of methylidyne radicals with hydrogen sulfide, leading to thioformaldehyde (H2CS) and its thiohydroxycarbene isomer (HCSH). The facile route to two of the simplest organosulfur molecules via a single-collision event affords persuasive evidence for a likely source of organosulfur molecules in star-forming regions. These fundamental reaction mechanisms are valuable to facilitate an understanding of the origin and evolution of the molecular universe and, in particular, of sulfur in our Galaxy.
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Affiliation(s)
| | - Chao He
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822
| | - Ralf I Kaiser
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822;
| | - Yuheng Luo
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822
| | - Rui Sun
- Department of Chemistry, University of Hawai'i at Mānoa, Honolulu, HI 96822;
| | - Galiya R Galimova
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199
| | - Alexander M Mebel
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199;
| | - Tom J Millar
- School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland, United Kingdom
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5
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Chang Y, Yang J, Chen Z, Zhang Z, Yu Y, Li Q, He Z, Zhang W, Wu G, Ingle RA, Bain M, Ashfold MNR, Yuan K, Yang X, Hansen CS. Ultraviolet photochemistry of ethane: implications for the atmospheric chemistry of the gas giants. Chem Sci 2020; 11:5089-5097. [PMID: 34122966 PMCID: PMC8159213 DOI: 10.1039/d0sc01746a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 04/29/2020] [Indexed: 11/23/2022] Open
Abstract
Chemical processing in the stratospheres of the gas giants is driven by incident vacuum ultraviolet (VUV) light. Ethane is an important constituent in the atmospheres of the gas giants in our solar system. The present work describes translational spectroscopy studies of the VUV photochemistry of ethane using tuneable radiation in the wavelength range 112 ≤ λ ≤ 126 nm from a free electron laser and event-triggered, fast-framing, multi-mass imaging detection methods. Contributions from at least five primary photofragmentation pathways yielding CH2, CH3 and/or H atom products are demonstrated and interpreted in terms of unimolecular decay following rapid non-adiabatic coupling to the ground state potential energy surface. These data serve to highlight parallels with methane photochemistry and limitations in contemporary models of the photoinduced stratospheric chemistry of the gas giants. The work identifies additional photochemical reactions that require incorporation into next generation extraterrestrial atmospheric chemistry models which should help rationalise hitherto unexplained aspects of the atmospheric ethane/acetylene ratios revealed by the Cassini-Huygens fly-by of Jupiter.
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Affiliation(s)
- Yao Chang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Jiayue Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Zhichao Chen
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Zhiguo Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
- Key Laboratory of Functional Materials and Devices for Informatics of Anhui Higher Education Institutions, School of Physics and Electronic Engineering, Fuyang Normal University Fuyang Anhui 236041 China
| | - Yong Yu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Qingming Li
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Zhigang He
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Weiqing Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Guorong Wu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Rebecca A Ingle
- Department of Chemistry, University College London London WC1H 0AJ UK
| | - Matthew Bain
- School of Chemistry, University of Bristol Bristol BS8 1TS UK
| | | | - Kaijun Yuan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences 457 Zhongshan Road Dalian 116023 China
- Department of Chemistry, Southern University of Science and Technology Shenzhen 518055 China
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6
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Gao H, Ng CY. Quantum state-to-state vacuum ultraviolet photodissociation dynamics of small molecules. CHINESE J CHEM PHYS 2019. [DOI: 10.1063/1674-0068/cjcp1812290] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Hong Gao
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Cheuk-Yiu Ng
- Department of Chemistry, University of California, Davis CA 95616, USA
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7
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Ashfold MNR, Ingle RA, Karsili TNV, Zhang J. Photoinduced C–H bond fission in prototypical organic molecules and radicals. Phys Chem Chem Phys 2019; 21:13880-13901. [DOI: 10.1039/c8cp07454b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We survey and assess current knowledge regarding the primary photochemistry of hydrocarbon molecules and radicals.
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Affiliation(s)
| | | | | | - Jingsong Zhang
- Department of Chemistry
- University of California at Riverside
- Riverside
- USA
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8
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Ashfold MNR, Yuan K, Yang X. Perspective: The development and applications of H Rydberg atom translational spectroscopy methods. J Chem Phys 2018; 149:080901. [PMID: 30193478 DOI: 10.1063/1.5047911] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Kaijun Yuan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
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9
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Hicks RK, Day DA, Jimenez JL, Tolbert MA. Follow the Carbon: Isotopic Labeling Studies of Early Earth Aerosol. ASTROBIOLOGY 2016; 16:822-830. [PMID: 27870584 DOI: 10.1089/ast.2015.1436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Despite the faint young Sun, early Earth might have been kept warm by an atmosphere containing the greenhouse gases CH4 and CO2 in mixing ratios higher than those found on Earth today. Laboratory and modeling studies suggest that an atmosphere containing these trace gases could lead to the formation of organic aerosol haze due to UV photochemistry. Chemical mechanisms proposed to explain haze formation rely on CH4 as the source of carbon and treat CO2 as a source of oxygen only, but this has not previously been verified experimentally. In the present work, we use isotopically labeled precursor gases and unit-mass resolution (UMR) and high-resolution (HR) aerosol mass spectrometry to examine the sources of carbon and oxygen to photochemical aerosol formed in a CH4/CO2/N2 atmosphere. UMR results suggest that CH4 contributes 70-100% of carbon in the aerosol, while HR results constrain the value from 94% to 100%. We also confirm that CO2 contributes approximately 10% of the total mass to the aerosol as oxygen. These results have implications for the geochemical interpretations of inclusions found in Archean rocks on Earth and for the astrobiological potential of other planetary atmospheres. Key Words: Atmosphere-Early Earth-Planetary atmospheres-Carbon dioxide-Methane. Astrobiology 16, 822-830.
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Affiliation(s)
- Raea K Hicks
- Department of Chemistry and Biochemistry, and Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado
| | - Douglas A Day
- Department of Chemistry and Biochemistry, and Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado
| | - Jose L Jimenez
- Department of Chemistry and Biochemistry, and Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado
| | - Margaret A Tolbert
- Department of Chemistry and Biochemistry, and Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado
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10
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Sebree JA, Stern JC, Mandt KE, Domagal-Goldman SD, Trainer MG. 13C and 15N fractionation of CH 4/N 2 mixtures during photochemical aerosol formation: Relevance to Titan. ICARUS 2015; 270:421-428. [PMID: 31068732 PMCID: PMC6501594 DOI: 10.1016/j.icarus.2015.04.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The ratios of the stable isotopes that comprise each chemical species in Titan's atmosphere provide critical information towards understanding the processes taking place within its modern and ancient atmosphere. Several stable isotope pairs, including 12C/13C and 14N/15N, have been measured in situ or probed spectroscopically by Cassini-borne instruments, space telescopes, or through ground-based observations. Current attempts to model the observed isotope ratios incorporate fractionation resulting from atmospheric diffusion, hydrodynamic escape, and primary photochemical processes. However, the effect of a potentially critical pathway for isotopic fractionation - organic aerosol formation and subsequent deposition onto the surface of Titan - has not been considered due to insufficient data regarding fractionation during aerosol formation. To better understand the nature of this process, we have conducted a laboratory study to measure the isotopic fractionation associated with the formation of Titan aerosol analogs, commonly referred to as 'tholins', via far-UV irradiation of several methane (CH4) and dinitrogen (N2) mixtures. Analysis of the δ13C and δ15N isotopic signatures of the photochemical aerosol products using an isotope ratio mass spectrometer (IRMS) show that fractionation direction and magnitude are dependent on the initial bulk composition of the gas mixture. In general, the aerosols showed enrichment in 13C and 14N, and the observed fractionation trends can provide insight into the chemical mechanisms controlling photochemical aerosol formation.
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Affiliation(s)
- Joshua A. Sebree
- University of Northern Iowa, Department of Chemistry and Biochemistry, Cedar Falls, IA 50614, USA
- NASA Goddard Space Flight Center, Solar System Exploration Division, Greenbelt, MD 20771, USA
| | - Jennifer C. Stern
- NASA Goddard Space Flight Center, Solar System Exploration Division, Greenbelt, MD 20771, USA
| | - Kathleen E. Mandt
- Space Science and Engineering Division, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78228, USA
| | | | - Melissa G. Trainer
- NASA Goddard Space Flight Center, Solar System Exploration Division, Greenbelt, MD 20771, USA
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11
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Wu C, Wu C, Fan Y, Xie X, Wang P, Deng Y, Liu Y, Gong Q. Three-body fragmentation of CO2 driven by intense laser pulses. J Chem Phys 2015; 142:124303. [DOI: 10.1063/1.4916045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Chengyin Wu
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, People’s Republic of China
| | - Cong Wu
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
| | - Yameng Fan
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
| | - Xiguo Xie
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
| | - Peng Wang
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
| | - Yongkai Deng
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
| | - Yunquan Liu
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, People’s Republic of China
| | - Qihuang Gong
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, People’s Republic of China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, People’s Republic of China
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12
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Bossa JB, Paardekooper DM, Isokoski K, Linnartz H. Methane ice photochemistry and kinetic study using laser desorption time-of-flight mass spectrometry at 20 K. Phys Chem Chem Phys 2015; 17:17346-54. [DOI: 10.1039/c5cp00578g] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Laser Desorption Post-Ionization Time-Of-Flight Mass Spectrometry is used to perform a systematic kinetic study on the pure methane photolysis in the condensed phase at 20 K and provides for the first time effective rate constants and branching ratios for primary processes leading to CH3, CH2, and CH radicals upon irradiation by VUV light in the 120–170 nm domain.
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Affiliation(s)
- J.-B. Bossa
- Raymond and Beverly Sackler Laboratory for Astrophysics
- Leiden Observatory
- Leiden University
- NL 2300 RA Leiden
- The Netherlands
| | - D. M. Paardekooper
- Raymond and Beverly Sackler Laboratory for Astrophysics
- Leiden Observatory
- Leiden University
- NL 2300 RA Leiden
- The Netherlands
| | - K. Isokoski
- Raymond and Beverly Sackler Laboratory for Astrophysics
- Leiden Observatory
- Leiden University
- NL 2300 RA Leiden
- The Netherlands
| | - H. Linnartz
- Raymond and Beverly Sackler Laboratory for Astrophysics
- Leiden Observatory
- Leiden University
- NL 2300 RA Leiden
- The Netherlands
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13
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Zhang M, Ma JQ, Han J, Dai HL. Collision Relaxation of Highly Vibrationally Excited SO2by CO in A Supersonic Beam. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200600003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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14
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Koseki S, Shimakura N, Teranishi Y, Lin SH, Fujimura Y. Neutral-fragmentation paths of methane induced by intense ultrashort IR laser pulses: ab initio molecular orbital approach. J Phys Chem A 2013; 117:333-41. [PMID: 23231683 DOI: 10.1021/jp309931c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Instantaneous (laser-field-dependent) potential energy curves leading to neutral fragmentations of methane were calculated at several laser intensities from 1.4 × 10(13) to 1.2 × 10(14) W/cm(2) (from 1.0 × 10(10) to 3.0 × 10(10) V/m) using ab initio molecular orbital (MO) methods to validate the observation of neutral fragmentations induced by intense femtosecond IR pulses (Kong et al. J. Chem. Phys. 2006, 125, 133320). Two fragmentation paths, CH(2) + 2H and CH(2) + H(2), in (1)T(2) superexcited states that are located in the energy range of 12-16 eV were considered as the reaction paths because these states are responsible for Jahn-Teller distortion opening up reaction paths during ultrashort pulses. As field intensity increased, the low-lying excited (1)A(1) states originated from the Jahn-Teller (1)T(2) states were substantially stabilized along the neutral-fragment path CH(4) → CH(2) + 2H and were located below the ionization threshold. On the other hand, the low-lying excited (1)B(1) states, which also originate from the Jahn-Teller (1)T(2) states, were embedded on the ionized state along the dissociation path to CH(2) + H(2). This indicates that ionic fragments, rather than neutral ones, are produced along the CH(2) + H(2) path. The computational results support neutral fragmentations through superexcited states proposed by Kong et al.
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Affiliation(s)
- Shiro Koseki
- Department of Chemistry, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai 599-8531, Japan
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15
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Blitz MA, Seakins PW. Laboratory studies of photochemistry and gas phase radical reaction kinetics relevant to planetary atmospheres. Chem Soc Rev 2012; 41:6318-47. [DOI: 10.1039/c2cs35204d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Ram NB, Krishnakumar E. Dissociative electron attachment to methane probed using velocity slice imaging. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.05.065] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Gans B, Boyé-Péronne S, Broquier M, Delsaut M, Douin S, Fellows CE, Halvick P, Loison JC, Lucchese RR, Gauyacq D. Photolysis of methane revisited at 121.6 nm and at 118.2 nm: quantum yields of the primary products, measured by mass spectrometry. Phys Chem Chem Phys 2011; 13:8140-52. [DOI: 10.1039/c0cp02627a] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Kaiser RI, Maksyutenko P, Ennis C, Zhang F, Gu X, Krishtal SP, Mebel AM, Kostko O, Ahmed M. Untangling the chemical evolution of Titan's atmosphere and surface–from homogeneous to heterogeneous chemistry. Faraday Discuss 2010; 147:429-78; discussion 527-52. [DOI: 10.1039/c003599h] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Ashfold MNR, King GA, Murdock D, Nix MGD, Oliver TAA, Sage AG. πσ* excited states in molecular photochemistry. Phys Chem Chem Phys 2010; 12:1218-38. [DOI: 10.1039/b921706a] [Citation(s) in RCA: 274] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Lodriguito MD, Lendvay G, Schatz GC. Trajectory surface-hopping study of methane photodissociation dynamics. J Chem Phys 2009; 131:224320. [DOI: 10.1063/1.3271242] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wilson EH, Atreya SK. Titan’s Carbon Budget and the Case of the Missing Ethane. J Phys Chem A 2009; 113:11221-6. [DOI: 10.1021/jp905535a] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eric H. Wilson
- Jet Propulsion Laboratory, 4800 Oak Grove Drive M/S 169-237, Pasadena, California 91109-8099, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143
| | - Sushil K. Atreya
- Jet Propulsion Laboratory, 4800 Oak Grove Drive M/S 169-237, Pasadena, California 91109-8099, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, Michigan 48109-2143
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22
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Derk AR, Funke HH, Falconer JL. Methane Conversion to Higher Hydrocarbons by UV Irradiation. Ind Eng Chem Res 2008. [DOI: 10.1021/ie0712840] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alan R. Derk
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309-0424
| | - Hans H. Funke
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309-0424
| | - John L. Falconer
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309-0424
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23
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Romanzin C, Gans B, Douin S, Boyé-Péronne S, Gauyacq D. 193nm photolysis of CHCl3: Probe of the CH product by CRDS. Chem Phys 2008. [DOI: 10.1016/j.chemphys.2008.03.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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24
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25
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Hébrard E, Dobrijevic M, Bénilan Y, Raulin F. Photochemical kinetics uncertainties in modeling Titan’s atmosphere: A review. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2006. [DOI: 10.1016/j.jphotochemrev.2006.12.004] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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27
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Loison JC, Bergeat A, Caralp F, Hannachi Y. Rate Constants and H Atom Branching Ratios of the Gas-Phase Reactions of Methylidyne CH(X2Π) Radical with a Series of Alkanes. J Phys Chem A 2006; 110:13500-6. [PMID: 17165876 DOI: 10.1021/jp065831r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reactions of the CH radical with several alkanes were studied, at room temperature, in a low-pressure fast-flow reactor. CH(X2Pi, v = 0) radicals were obtained from the reaction of CHBr(3) with potassium atoms. The overall rate constants at 300 K are (0.76 +/- 0.20) x 10(-10) [Fleurat-Lessard, P.; Rayez, J. C.; Bergeat, A.; Loison, J. C. Chem. Phys. 2002, 279, 87],1 (1.60 +/- 0.60) x 10(-10)[Galland, N.; Caralp, F.; Hannachi, Y.; Bergeat, A.; Loison, J.-C. J. Phys. Chem. A 2003, 107, 5419],2 (2.20 +/- 0.80) x 10(-10), (2.80 +/- 0.80) x 10(-10), (3.20 +/- 0.80) x 10(-10), (3.30 +/- 0.60) x 10(-10), and (3.60 +/- 0.80) x 10(-10) cm3 molecule(-1) s(-1), (errors refer to +/-2sigma) for methane, ethane, propane, n-butane, n-pentane, neo-pentane, and n-hexane respectively. The experimental overall rate constants correspond to those obtained using a simple classical capture theory. Absolute atomic hydrogen production was determined by V.U.V. resonance fluorescence, with H production from the CH + CH4 reaction being used as a reference. Observed H branching ratios were for CH4, 1.00[Fleurat-Lessard, P.; Rayez, J. C.; Bergeat, A.; Loison, J. C. Chem. Phys. 2002, 279, 87];1 C(2)H(6), 0.22 +/- 0.08 [Galland, N.; Caralp, F.; Hannachi, Y.; Bergeat, A.; Loison, J.-C. J. Phys. Chem. A 2003, 107, 5419];2 C(3)H(8), 0.19 +/- 0.07; C(4)H(10) (n-butane), 0.14 +/- 0.06; C(5)H(12) (n-pentane), 0.52 +/- 0.08; C(5)H(12) (neo-pentane), 0.51 +/- 0.08; C(5)H(12) (iso-pentane), 0.12 +/- 0.06; C(6)H(14) (n-hexane), 0.06 +/- 0.04.
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Affiliation(s)
- Jean-Christophe Loison
- Laboratoire de Physico-Chimie Moléculaire, CNRS UMR 5803, Université Bordeaux I, F-33405 Talence Cedex, France.
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28
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Kong F, Luo Q, Xu H, Sharifi M, Song D, Chin SL. Explosive photodissociation of methane induced by ultrafast intense laser. J Chem Phys 2006; 125:133320. [PMID: 17029473 DOI: 10.1063/1.2204919] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A new type of molecular fragmentation induced by femtosecond intense laser at the intensity of 2 x 10(14) W/cm2 is reported. For the parent molecule of methane, ethylene, n-butane, and 1-butene, fluorescence from H (n = 3-->2), CH (A 2Delta, B 2Sigma-, and C 2Sigma+-->X 2Pi), or C2 (d 3Pi g-->a 3Pi u) is observed in the spectrum. It shows that the fragmentation is a universal property of neutral molecule in the intense laser field. Unlike breaking only one or two chemical bonds in conventional UV photodissociation, the fragmentation caused by the intense laser undergoes vigorous changes, breaking most of the bonds in the molecule, like an explosion. The fragments are neutral species and cannot be produced through Coulomb explosion of multiply charged ion. The laser power dependence of CH (A-->X) emission of methane on a log-log scale has a slope of 10 +/- 1. The fragmentation is thus explained as multiple channel dissociation of the superexcited state of parent molecule, which is created by multiphoton excitation.
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Affiliation(s)
- Fanao Kong
- Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
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van Harrevelt R. Photodissociation of methane: Exploring potential energy surfaces. J Chem Phys 2006; 125:124302. [PMID: 17014169 DOI: 10.1063/1.2335441] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The potential energy surface for the first excited singlet state (S(1)) of methane is explored using multireference singles and doubles configuration interaction calculations, employing a valence triple zeta basis set. A larger valence quadruple zeta basis is used to calculate the vertical excitation energy and dissociation energies. All stationary points found on the S(1) surface are saddle points and have imaginary frequencies for symmetry-breaking vibrations. By studying several two-dimensional cuts through the potential energy surfaces, it is argued that CH(4) in the S(1) state will distort to planar structures. Several conical intersection seams between the ground state surface S(0) and the S(1) surface have been identified at planar geometries. The conical intersections provide electronically nonadiabatic pathways towards products CH(3)((approximately)X (2)A"(2))+H, CH(2)((approximately)a (1)A(1))+H(2), or CH(2)((approximately)X (3)B(1))+H+H. The present results thereby make it plausible that the CH(3)((approximately)X (2)A"(2))+H and CH(2)((approximately)a (1)A(1))+H(2) channels are major dissociation channels, as has been observed experimentally.
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Affiliation(s)
- Rob van Harrevelt
- Instituut voor Theoretische Chemie, Radboud Universiteit Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, The Netherlands.
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Goulay F, Rebrion-Rowe C, Biennier L, Le Picard SD, Canosa A, Rowe BR. Reaction of Anthracene with CH Radicals: An Experimental Study of the Kinetics between 58 and 470 K. J Phys Chem A 2005; 110:3132-7. [PMID: 16509636 DOI: 10.1021/jp054537g] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The rate coefficient of the reaction of the methylidine radical CH with anthracene has been studied over a wide temperature range (58-470 K) in a dedicated "Cinétique de Réaction en Ecoulement Supersonique Uniforme" (Reaction Kinetics in Uniform Supersonic Flow) apparatus. The reaction exhibits a slight positive temperature dependence, which can be fitted to the expression k(T) = (3.32 +/- 1.00) x 10(-10)(T/298)((0.46+/-0.14)) cm3 molecule(-1) s(-1). Even at the lowest temperature, the reaction remains very fast indicating that the kinetics are probably driven by a capture process.
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Affiliation(s)
- Fabien Goulay
- Laboratoire PALMS, Equipe Astrochimie Expérimentale, UMR 6627 CNRS-Université, Université de RENNES I, Bat. 11C, Campus de Beaulieu, 35042 Rennes Cedex, France.
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31
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Wilson EH. Current state of modeling the photochemistry of Titan's mutually dependent atmosphere and ionosphere. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003je002181] [Citation(s) in RCA: 285] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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32
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Qadiri RH, Feltham EJ, Hendrik Nahler N, Pérez Garcı́a R, Ashfold MNR. Propyne and allene photolysis at 193.3 nm and at 121.6 nm. J Chem Phys 2003. [DOI: 10.1063/1.1627761] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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33
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Zhang M, Han J, Liu P, Muller D, Dai HL. Collision Induced Dephasing in Fluorescence Quantum Beat of SO2(C̃B2). J Phys Chem A 2003. [DOI: 10.1021/jp030957z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Min Zhang
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Jun Han
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Peng Liu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Don Muller
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
| | - Hai-Lung Dai
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
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Wang CC, Lee YT, Lin JJ, Shu J, Lee YY, Yang X. Photodissociation dynamics of cyclopropane at 157 nm. J Chem Phys 2002. [DOI: 10.1063/1.1481390] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Pavlov AA, Brown LL, Kasting JF. UV shielding of NH3and O2by organic hazes in the Archean atmosphere. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001448] [Citation(s) in RCA: 203] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Amaral G, Xu K, Zhang J. H-Atom Product Channels in the Photodissociation of CH3Cl, CH3Br, and CH3I at 121.6 nm. J Phys Chem A 2001. [DOI: 10.1021/jp0028507] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gabriel Amaral
- Department of Chemistry, University of California, Riverside, California 92521
| | - Kesheng Xu
- Department of Chemistry, University of California, Riverside, California 92521
| | - Jingsong Zhang
- Department of Chemistry, University of California, Riverside, California 92521
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38
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Michelsen HA, Simpson WR. Relating State-Dependent Cross Sections to Non-Arrhenius Behavior for the Cl + CH4 Reaction. J Phys Chem A 2000. [DOI: 10.1021/jp0016784] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Hope A. Michelsen
- Combustion Research Facility, Sandia National Laboratories, MS 9055, P.O. Box 969, Livermore, California 94551
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Wilson EH, Atreya SK. Sensitivity studies of methane photolysis and its impact on hydrocarbon chemistry in the atmosphere of Titan. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001221] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lee AYT, Yung YL, Moses J. Photochemical modeling of CH3abundances in the outer solar system. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001186] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Wu SM, Lin JJ, Lee YT, Yang X. Dynamics of Atomic and Molecular Hydrogen Elimination from Small Alkanes Following 157-nm Excitation. J Phys Chem A 2000. [DOI: 10.1021/jp0004056] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. M. Wu
- Department of Chemistry, National Taiwan University, Taipei, Taiwan, Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, and Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - J. J. Lin
- Department of Chemistry, National Taiwan University, Taipei, Taiwan, Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, and Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Y. T. Lee
- Department of Chemistry, National Taiwan University, Taipei, Taiwan, Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, and Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - X. Yang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan, Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, and Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
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Lee S, Samuels DA, Hoobler RJ, Leone SR. Direct measurements of rate coefficients for the reaction of ethynyl radical (C2H) with C2H2at 90 and 120 K using a pulsed Laval nozzle apparatus. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001187] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wu SM, Lin JJ, Lee YT, Yang X. Site specificity in molecular hydrogen elimination from photodissociation of propane at 157 nm. J Chem Phys 1999. [DOI: 10.1063/1.479507] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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A box model of the photolysis of methane at 123.6 and 147nm—comparison between model and experiment. J Photochem Photobiol A Chem 1999. [DOI: 10.1016/s1010-6030(99)00074-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Min Z, Wong TH, Bersohn R. Hydrogen atom release from methyl groups of energized molecules. J Chem Phys 1999. [DOI: 10.1063/1.478868] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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46
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47
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Smith NS, Raulin F. Modeling of methane photolysis in the reducing atmospheres of the outer solar system. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1998je900027] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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48
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Regan PM, Langford SR, Orr-Ewing AJ, Ashfold MNR. The ultraviolet photodissociation dynamics of hydrogen bromide. J Chem Phys 1999. [DOI: 10.1063/1.478063] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wang JH, Liu K. VUV photochemistry of CH4 and isotopomers. I. Dynamics and dissociation pathway of the H/D-atom elimination channel. J Chem Phys 1998. [DOI: 10.1063/1.477394] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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50
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Löffler P, Wrede E, Schnieder L, Halpern JB, Jackson WM, Welge KH. Dissociation dynamics of acetylene Rydberg states as a function of excited state lifetime. J Chem Phys 1998. [DOI: 10.1063/1.477140] [Citation(s) in RCA: 31] [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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