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Yu Y, Jiang J, Hua L, Chen C, Xu Y, Chen P, Wang W, Chen Y, Fan Z, Li H. Ionization of Dichloromethane by a Vacuum Ultraviolet Krypton Lamp: Competition Between Photoinduced Ion-Pair and Photodissociation-Assisted Photoionization. J Phys Chem Lett 2023; 14:1265-1271. [PMID: 36719712 DOI: 10.1021/acs.jpclett.2c03572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The photodissociation and photoionization behaviors of haloalkanes in the VUV regime are important to fully understand the mechanism of ozone depletion in the stratosphere. The ionization of dichloromethane (CH2Cl2) under the irradiation of 10.0 and 10.6 eV light was investigated. CH2Cl+ was observed at 10 Pa, while both CH2Cl+ and CHCl2+ were observed at higher pressure. The production efficiency of CH2Cl+ decreased with the increasing number density of CH2Cl2, while that of CHCl2+ increased. A kinetic model was successfully derived to quantitatively describe the variation trends of CH2Cl+ and CHCl2+, in which the competition between photoinduced ion-pair and photodissociation-assisted photoionization (PD-PI) were included. The ion-pair channel was quenched efficiently at higher pressure or concentration, which reduced its contribution. Our study proposed new insights into the complicated photoexcitation behaviors of CH2Cl2 in the VUV regime and revealed the important role of photodissociation in photoionization at low photon flux.
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Affiliation(s)
- Yi Yu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
- University of Chinese Academy of Sciences, Beijing100049, People's Republic of China
| | - Jichun Jiang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
| | - Lei Hua
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
| | - Chuang Chen
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
| | - Yiqian Xu
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
- University of Chinese Academy of Sciences, Beijing100049, People's Republic of China
| | - Ping Chen
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
| | - Weiguo Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
| | - Yi Chen
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
- University of Chinese Academy of Sciences, Beijing100049, People's Republic of China
| | - Zhigang Fan
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
- University of Chinese Academy of Sciences, Beijing100049, People's Republic of China
| | - Haiyang Li
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning116023, People's Republic of China
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2
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Donovan RJ, Kirrander A, Lawley KP. Heavy Rydberg and ion-pair states: chemistry, spectroscopy and theory. INT REV PHYS CHEM 2022. [DOI: 10.1080/0144235x.2022.2077024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Robert J. Donovan
- School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
| | - Adam Kirrander
- School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
| | - Kenneth P. Lawley
- School of Chemistry, University of Edinburgh, Edinburgh, United Kingdom
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3
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Kivimäki A, Stråhlman C, Sankari R, Richter R. Negative-ion/positive-ion coincidence spectroscopy as a tool to identify anionic fragments: The case of core-excited CHF 3. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 55:e4487. [PMID: 31826309 DOI: 10.1002/jms.4487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
We have studied the dissociation of the trifluoromethane molecule, CHF3 , into negative ionic fragments at the C 1s and F 1s edges. The measurements were performed by detecting coincidences between negative and positive ions. We observed five different negative ions: F- , H- , C- , CF- , and F2 - . Their production was confirmed by the analysis of triple coincidence events (negative-ion/positive-ion/positive-ion or NIPIPI coincidences) that were recorded with cleaner signals than those of the negative-ion/positive-ion coincidences. The intensities of the most intense NIPIPI coincidence channels were recorded as a function of photon energy across the C 1s and F 1s excitations and ionization thresholds. We also observed dissociation channels involving the formation of one negative ion and three positive ions. Our results demonstrate that negative-ion/positive-ion coincidence spectroscopy is a very sensitive method to observe anions, which at inner-shell edges are up to three orders of magnitude less probable dissociation products than cations.
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Affiliation(s)
- Antti Kivimäki
- Nano and Molecular Systems Research Unit, University of Oulu, 90014 Oulu, Finland
- MAX IV Laboratory, Lund University, 22100 Lund, Sweden
| | - Christian Stråhlman
- MAX IV Laboratory, Lund University, 22100 Lund, Sweden
- Department of Materials Science and Applied Mathematics, Malmö University, 20506 Malmö, Sweden
| | - Rami Sankari
- MAX IV Laboratory, Lund University, 22100 Lund, Sweden
- Surface Science Group, Laboratory of Photonics, Physics Unit, Tampere University, 33014 Tampere, Finland
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4
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Lischka H, Shepard R, Müller T, Szalay PG, Pitzer RM, Aquino AJA, Araújo do Nascimento MM, Barbatti M, Belcher LT, Blaudeau JP, Borges I, Brozell SR, Carter EA, Das A, Gidofalvi G, González L, Hase WL, Kedziora G, Kertesz M, Kossoski F, Machado FBC, Matsika S, do Monte SA, Nachtigallová D, Nieman R, Oppel M, Parish CA, Plasser F, Spada RFK, Stahlberg EA, Ventura E, Yarkony DR, Zhang Z. The generality of the GUGA MRCI approach in COLUMBUS for treating complex quantum chemistry. J Chem Phys 2020; 152:134110. [PMID: 32268762 DOI: 10.1063/1.5144267] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The core part of the program system COLUMBUS allows highly efficient calculations using variational multireference (MR) methods in the framework of configuration interaction with single and double excitations (MR-CISD) and averaged quadratic coupled-cluster calculations (MR-AQCC), based on uncontracted sets of configurations and the graphical unitary group approach (GUGA). The availability of analytic MR-CISD and MR-AQCC energy gradients and analytic nonadiabatic couplings for MR-CISD enables exciting applications including, e.g., investigations of π-conjugated biradicaloid compounds, calculations of multitudes of excited states, development of diabatization procedures, and furnishing the electronic structure information for on-the-fly surface nonadiabatic dynamics. With fully variational uncontracted spin-orbit MRCI, COLUMBUS provides a unique possibility of performing high-level calculations on compounds containing heavy atoms up to lanthanides and actinides. Crucial for carrying out all of these calculations effectively is the availability of an efficient parallel code for the CI step. Configuration spaces of several billion in size now can be treated quite routinely on standard parallel computer clusters. Emerging developments in COLUMBUS, including the all configuration mean energy multiconfiguration self-consistent field method and the graphically contracted function method, promise to allow practically unlimited configuration space dimensions. Spin density based on the GUGA approach, analytic spin-orbit energy gradients, possibilities for local electron correlation MR calculations, development of general interfaces for nonadiabatic dynamics, and MRCI linear vibronic coupling models conclude this overview.
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Affiliation(s)
- Hans Lischka
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Ron Shepard
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Thomas Müller
- Institute for Advanced Simulation, Jülich Supercomputing Centre, Forschungszentrum Jülich, Jülich 52428, Germany
| | - Péter G Szalay
- ELTE Eötvös Loránd University, Institute of Chemistry, Budapest, Hungary
| | - Russell M Pitzer
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | - Adelia J A Aquino
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin 300072, People's Republic of China
| | | | | | - Lachlan T Belcher
- Laser and Optics Research Center, Department of Physics, US Air Force Academy, Colorado 80840, USA
| | | | - Itamar Borges
- Departamento de Química, Instituto Militar de Engenharia, Rio de Janeiro, RJ 22290-270, Brazil
| | - Scott R Brozell
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Emily A Carter
- Office of the Chancellor and Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Box 951405, Los Angeles, California 90095-1405, USA
| | - Anita Das
- Indian Institute of Engineering Science and Technology, Shibpur, Howrah, India
| | - Gergely Gidofalvi
- Department of Chemistry and Biochemistry, Gonzaga University, Spokane, Washington 99258, USA
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| | - William L Hase
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Gary Kedziora
- Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, USA
| | - Miklos Kertesz
- Department of Chemistry, Georgetown University, 37th and O Streets, NW, Washington, DC 20057-1227, USA
| | | | - Francisco B C Machado
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 12228-900, São Paulo, Brazil
| | - Spiridoula Matsika
- Department of Chemistry, Temple University, 1901 N. 13th St., Philadelphia, Pennsylvania 19122, USA
| | | | - Dana Nachtigallová
- Institute of Organic Chemistry and Biochemistry v.v.i., The Czech Academy of Sciences, Flemingovo nám. 2, 160610 Prague 6, Czech Republic
| | - Reed Nieman
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA
| | - Markus Oppel
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| | - Carol A Parish
- Department of Chemistry, Gottwald Center for the Sciences, University of Richmond, Richmond, Virginia 23173, USA
| | - Felix Plasser
- Department of Chemistry, Loughborough University, Loughborough LE11 3TU, United Kingdom
| | - Rene F K Spada
- Departamento de Física, Instituto Tecnológico de Aeronáutica, São José dos Campos 12228-900, São Paulo, Brazil
| | - Eric A Stahlberg
- Biomedical Informatics and Data Science, Frederick National Laboratory for Cancer Research, Frederick, Maryland 21702, USA
| | - Elizete Ventura
- Universidade Federal da Paraíba, 58059-900 João Pessoa, PB, Brazil
| | - David R Yarkony
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, USA
| | - Zhiyong Zhang
- Stanford Research Computing Center, Stanford University, 255 Panama Street, Stanford, California 94305, USA
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5
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Hydrogen-bonded contact ion pair in gaseous chloroethane: a multi-reference configuration interaction with singles and doubles (MR-CISD) study including extensivity corrections. Theor Chem Acc 2020. [DOI: 10.1007/s00214-020-2561-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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6
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Pereira Rodrigues G, Lopes de Lima TM, de Andrade RB, Ventura E, do Monte SA, Barbatti M. Photoinduced Formation of H-Bonded Ion Pair in HCFC-133a. J Phys Chem A 2019; 123:1953-1961. [DOI: 10.1021/acs.jpca.8b12482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gessenildo Pereira Rodrigues
- Universidade Federal da Paraíba, 58059-900, João Pessoa-PB, Brazil
- Faculdade Rebouças, 58406-040, Campina Grande-PB, Brazil
| | | | | | - Elizete Ventura
- Universidade Federal da Paraíba, 58059-900, João Pessoa-PB, Brazil
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7
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Yang B, Zhang H, Shu J, Ma P, Zhang P, Huang J, Li Z, Xu C. Vacuum-Ultraviolet-Excited and CH2Cl2/H2O-Amplified Ionization-Coupled Mass Spectrometry for Oxygenated Organics Analysis. Anal Chem 2017; 90:1301-1308. [DOI: 10.1021/acs.analchem.7b04122] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Bo Yang
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Haixu Zhang
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Jinian Shu
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Pengkun Ma
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Peng Zhang
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Jingyun Huang
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Zhen Li
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Ce Xu
- State
Key Laboratory of Environment Simulation and Pollution Control, Research
Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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Affiliation(s)
| | - Catherine Walsh
- Leiden
Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands
- School
of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
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9
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Baer T, Tuckett RP. Advances in threshold photoelectron spectroscopy (TPES) and threshold photoelectron photoion coincidence (TPEPICO). Phys Chem Chem Phys 2017; 19:9698-9723. [DOI: 10.1039/c7cp00144d] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The history and evolution of molecular threshold photoelectron spectroscopy and threshold photoelectron photoion coincidence spectroscopy (TPEPICO) over the last fifty years are reviewed.
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Affiliation(s)
- Tomas Baer
- Chemistry Department
- University of North Carolina
- Chapel Hill
- USA
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10
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Poretskiy MS, Chichinin AI, Maul C, Gericke KH. Double-arm three-dimensional ion imaging apparatus for the study of ion pair channels in resonance enhanced multiphoton ionization. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:023107. [PMID: 26931834 DOI: 10.1063/1.4936984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present a novel experimental configuration for the full quantitative characterization of the multichannel resonance enhanced multiphoton ionization (REMPI) of small molecules in cases when the ion-pair dissociation channel is important. For this purpose, a double-arm time-of-flight mass spectrometer with three-dimensional (3D) ion imaging detectors at both arms is constructed. The REMPI of HCl molecules is used to examine the constructed setup. The apparatus allows us to perform simultaneous measurements of the 3D velocity vector distributions of positive (H(+), HCl(+), and Cl(+)) and negative (Cl(-)) photoions. The characterization consists of the determination of "two-photon absorption cross sections" for the process HCl(X)+2hν → HCl*, one-photon absorption cross sections for subsequent processes HCl* + hν → HCl*, and the probability of the subsequent non-adiabatic transition HCl* → HCl(B) → H(+) + Cl(-), which leads to ionic pairs. All these data should be obtained from the analysis of the dependencies of the number of ions on the laser energy. The full characterization of the laser beam and the knowledge of the ion detection probability are necessary parts of the analysis. Detailed knowledge of losses of produced ions in the mass spectrometer before detection requires understanding and characterization of such processes like electron emission from metallic grids under ion bombardment or charge transfer between positive ions and the metal surface of the grids, like Cl(+) + (grid) → Cl(-). These important phenomena from surface science are rarely discussed in the imaging literature, and here, we try to compensate for this shortcoming.
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Affiliation(s)
- M S Poretskiy
- Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - A I Chichinin
- Institute of Chemical Kinetics and Combustion and Novosibirsk State University, 630090 Novosibirsk, Russia
| | - C Maul
- Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - K-H Gericke
- Institut für Physikalische und Theoretische Chemie, Technische Universität Braunschweig, 38106 Braunschweig, Germany
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11
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Stråhlman C, Sankari R, Kivimäki A, Richter R, Coreno M, Nyholm R. A tandem time-of-flight spectrometer for negative-ion/positive-ion coincidence measurements with soft x-ray excitation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:013109. [PMID: 26827311 DOI: 10.1063/1.4940425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present a newly constructed spectrometer for negative-ion/positive-ion coincidence spectroscopy of gaseous samples. The instrument consists of two time-of-flight ion spectrometers and a magnetic momentum filter for deflection of electrons. The instrument can measure double and triple coincidences between mass-resolved negative and positive ions with high detection efficiency. First results include identification of several negative-ion/positive-ion coincidence channels following inner-shell photoexcitation of sulfur hexafluoride (SF6).
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Affiliation(s)
| | - Rami Sankari
- MAX IV Laboratory, Lund University, P.O. Box 118, 22100 Lund, Sweden
| | - Antti Kivimäki
- Consiglio Nazionale delle Ricerche-Istituto Officina dei Materiali, Laboratorio TASC, 34149 Trieste, Italy
| | - Robert Richter
- Elettra-Sincrotrone Trieste, Area Science Park, 34149 Trieste, Italy
| | - Marcello Coreno
- Consiglio Nazionale delle Ricerche-Istituto di Struttura della Materia, 34149 Trieste, Italy
| | - Ralf Nyholm
- MAX IV Laboratory, Lund University, P.O. Box 118, 22100 Lund, Sweden
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12
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de Medeiros VC, de Andrade RB, Leitão EFV, Ventura E, Bauerfeldt GF, Barbatti M, do Monte SA. Photochemistry of CH3Cl: Dissociation and CH···Cl Hydrogen Bond Formation. J Am Chem Soc 2015; 138:272-80. [PMID: 26653216 DOI: 10.1021/jacs.5b10573] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
State-of-the-art electronic structure calculations (MR-CISD) are used to map five different dissociation channels of CH3Cl along the C-Cl coordinate: (i) CH3(X̃(2)A2″) + Cl((2)P), (ii) CH3(3s(2)A1') + Cl((2)P), (iii) CH3(+)((1)A1') + Cl(-)((1)S), (iv) CH3(3p(2)E') + Cl((2)P), and (v) CH3(3p(2)A2″) + Cl((2)P). By the first time these latter four dissociation channels, accessible upon VUV absorption, are described. The corresponding dissociation limits, obtained at the MR-CISD+Q level, are 3.70, 9.50, 10.08, 10.76, and 11.01 eV. The first channel can be accessed through nσ* and n3s states, while the second channel can be accessed through n(e)3s, n(e)3p(σ), and σ3s states. The third channel, corresponding to the CH3(+) + Cl(-) ion-pair, is accessed through n(e)3p(e) states. The fourth is accessed through n(e)3p(e), n(e)3p(σ), and σ3p(σ), while the fifth through σ3p(e) and σ(CH)σ* states. The population of the diverse channels is controlled by two geometrical spots, where intersections between multiple states allow a cascade of nonadiabatic events. The ion-pair dissociation occurs through formation of CH3(+)···Cl(-)and H2CH(+)···Cl(-) intermediate complexes bound by 3.69 and 4.65 eV. The enhanced stability of the H2CH(+)···Cl(-) complex is due to a CH···Cl hydrogen bond. A time-resolved spectroscopic setup is proposed to detect those complexes.
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Affiliation(s)
- Vanessa C de Medeiros
- Departamento de Química, CCEN, Universidade Federal da Paraíba , João Pessoa, PB 58059-900, Brazil
| | - Railton B de Andrade
- Departamento de Química, CCEN, Universidade Federal da Paraíba , João Pessoa, PB 58059-900, Brazil
| | - Ezequiel F V Leitão
- Departamento de Química, CCEN, Universidade Federal da Paraíba , João Pessoa, PB 58059-900, Brazil
| | - Elizete Ventura
- Departamento de Química, CCEN, Universidade Federal da Paraíba , João Pessoa, PB 58059-900, Brazil
| | - Glauco F Bauerfeldt
- Departamento de Química, Instituto de Ciências Exatas, UFRRJ, Pavilhão Roberto Alvahydo (PQ) , sala 44. km 7, Rodovia Br 465, Seropédica, RJ 23890-000, Brazil
| | - Mario Barbatti
- Aix Marseille Université , CNRS, ICR UMR7273, 13397 Marseille, France
| | - Silmar A do Monte
- Departamento de Química, CCEN, Universidade Federal da Paraíba , João Pessoa, PB 58059-900, Brazil
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13
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Bodi A, Hemberger P, Gerber T, Sztáray B. A new double imaging velocity focusing coincidence experiment: i2PEPICO. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:083105. [PMID: 22938272 DOI: 10.1063/1.4742769] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The vacuum ultraviolet (VUV) beamline of the Swiss Light Source has been upgraded after two years of operation. A new, turntable-type monochromator was constructed at the Paul Scherrer Institut, which allows for fast yaw-alignment as well as quick grating change and exchange. In addition to the original imaging photoelectron photoion coincidence endstation (iPEPICO), a second, complementary double imaging setup (i(2)PEPICO) has been built. Volatile samples can be introduced at room temperature or in a molecular beam, a pyrolysis source allows for radical production, and non-volatile solids can be evaporated in a heated cell. Monochromatic VUV radiation ionizes the sample and both photoelectrons and photoions are velocity map imaged onto two fast position sensitive detectors and detected in delayed coincidence. High intensity synchrotron radiation leads to ionization rates above 10(5) s(-1). New data acquisition and processing approaches are discussed for recording coincidence processes at high rates. The setup is capable of resolving pulsed molecular beam profiles and the synchrotron time structure temporally. The latter is shown by photoelectron autocorrelation, which displays both the 1.04 MHz ring clock frequency as well as resolving the micro-pulses with a separation of 2 ns. Kinetic energy release analysis on the dissociative photoionization of CF(4) indicates a dissociation mechanism change in the Franck-Condon allowed energy range of the first ion state.
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Affiliation(s)
- Andras Bodi
- Paul Scherrer Institut, Villigen 5232, Switzerland.
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14
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Tian SX. Photoion-pair dissociation dynamics of polyatomic molecules with synchrotron radiation. Phys Chem Chem Phys 2012; 14:6433-43. [DOI: 10.1039/c2cp23763f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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