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Walmsley T, Unwin J, Allum F, Bari S, Boll R, Borne K, Brouard M, Bucksbaum P, Ekanayake N, Erk B, Forbes R, Howard AJ, Eng-Johnsson P, Lee JWL, Liu Z, Manschwetus B, Mason R, Passow C, Peschel J, Rivas D, Rolles D, Rörig A, Rouzée A, Vallance C, Ziaee F, Burt M. Characterizing the multi-dimensional reaction dynamics of dihalomethanes using XUV-induced Coulomb explosion imaging. J Chem Phys 2023; 159:144302. [PMID: 37823458 DOI: 10.1063/5.0172749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 09/27/2023] [Indexed: 10/13/2023] Open
Abstract
Site-selective probing of iodine 4d orbitals at 13.1 nm was used to characterize the photolysis of CH2I2 and CH2BrI initiated at 202.5 nm. Time-dependent fragment ion momenta were recorded using Coulomb explosion imaging mass spectrometry and used to determine the structural dynamics of the dissociating molecules. Correlations between these fragment momenta, as well as the onset times of electron transfer reactions between them, indicate that each molecule can undergo neutral three-body photolysis. For CH2I2, the structural evolution of the neutral molecule was simultaneously characterized along the C-I and I-C-I coordinates, demonstrating the sensitivity of these measurements to nuclear motion along multiple degrees of freedom.
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Affiliation(s)
- T Walmsley
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - J Unwin
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - F Allum
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - S Bari
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - R Boll
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - K Borne
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Brouard
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - P Bucksbaum
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - N Ekanayake
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - B Erk
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - R Forbes
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - A J Howard
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - P Eng-Johnsson
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - J W L Lee
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Z Liu
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - B Manschwetus
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - R Mason
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - C Passow
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - J Peschel
- Department of Physics, Lund University, 22100 Lund, Sweden
| | - D Rivas
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - D Rolles
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - A Rörig
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - A Rouzée
- Max-Born-Institute, Max-Born-Straße 2A, 12489 Berlin, Germany
| | - C Vallance
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - F Ziaee
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
| | - M Burt
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
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Casavola AR, Cartoni A, Castrovilli MC, Borocci S, Bolognesi P, Chiarinelli J, Catone D, Avaldi L. VUV Photofragmentation of Chloroiodomethane: The Iso-CH 2I-Cl and Iso-CH 2Cl-I Radical Cation Formation. J Phys Chem A 2020; 124:7491-7499. [PMID: 32786965 PMCID: PMC8010789 DOI: 10.1021/acs.jpca.0c05754] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Dihalomethanes
XCH2Y (X and Y = F, Cl, Br, and I) are a class of compounds
involved in several processes leading to the release of halogen atoms,
ozone consumption, and aerosol particle formation. Neutral dihalomethanes
have been largely studied, but chemical physics properties and processes
involving their radical ions, like the pathways of their decomposition,
have not been completely investigated. In this work the photodissociation
dynamics of the ClCH2I molecule has been explored in the
photon energy range 9–21 eV using both VUV rare gas discharge
lamps and synchrotron radiation. The experiments show that, among
the different fragment ions, CH2I+ and CH2Cl+, which correspond to the Cl- and I-losses,
respectively, play a dominant role. The experimental ionization energy
of ClCH2I and the appearance energies of the CH2I+ and CH2Cl+ ions are in agreement
with the theoretical results obtained at the MP2/CCSD(T) level of
theory. Computational investigations have been also performed to study
the isomerization of geminal [ClCH2I]•+ into the iso-chloroiodomethane isomers: [CH2I–Cl]•+ and [CH2Cl–I]•+.
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Affiliation(s)
- Anna Rita Casavola
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy
| | - Antonella Cartoni
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy.,Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Mattea Carmen Castrovilli
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy
| | - Stefano Borocci
- Department for Innovation in Biological, Agrofood and Forest Systems, University of Tuscia, Viterbo 01100, Italy.,Institute for Biological Systems-CNR (ISB-CNR), Area della Ricerca di Roma 1, Via Salaria, Km 29.500,, 00015 Monterotondo, Italy
| | - Paola Bolognesi
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy
| | - Jacopo Chiarinelli
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy
| | - Daniele Catone
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Tor Vergata, Via del Fosso del Cavaliere, 00133 Rome, Italy
| | - Lorenzo Avaldi
- Institute of Structure of Matter-CNR (ISM-CNR), Area della Ricerca di Roma 1, Via Salaria km 29.300, 00015 Monterotondo, Italy
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