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Vinklárek IS, Suchan J, Rakovský J, Moriová K, Poterya V, Slavíček P, Fárník M. Energy partitioning and spin-orbit effects in the photodissociation of higher chloroalkanes. Phys Chem Chem Phys 2021; 23:14340-14351. [PMID: 34169306 DOI: 10.1039/d1cp01371h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigate the photodissociation dynamics of the C-Cl bond in chloroalkanes CH3Cl, n-C3H7Cl, i-C3H7Cl, n-C5H11Cl, combining velocity map imaging (VMI) experiment and direct ab initio dynamical simulations. The Cl fragment kinetic energy distributions (KEDs) from the VMI experiment exhibit a single peak with maximum close to 0.8 eV, irrespective of the alkyl chain length and C-Cl bond position. In contrary to CH3Cl, where less than 10% of the available energy is deposited into the internal excitation of the CH3 fragment, for all higher chloroalkanes around 40% to 60% of the available energy goes into the alkyl fragment excitation. We apply the classical hard spheres and spectator model to explain the energy partitioning, and compare the classical approach with direct ab initio dynamics simulations. The alkyl chain appears to be a soft, energy absorbing unit. We further investigate the role of the spin-orbit effects on the excitation and dynamics. Combining our experimental data with theory allows us to derive the probability of the direct absorption into the triplet electronic state as well as the probabilities for intersystem crossing. The results indicate an increasing direct absorption into the triplet state with increasing alkyl chain length.
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Affiliation(s)
- Ivo S Vinklárek
- J. Heyrovský Institute of Physical Chemistry, v.v.i., The Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
| | - Jiří Suchan
- University of Chemistry and Technology, 166 28 Prague 6, Czech Republic.
| | - Jozef Rakovský
- J. Heyrovský Institute of Physical Chemistry, v.v.i., The Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
| | - Kamila Moriová
- J. Heyrovský Institute of Physical Chemistry, v.v.i., The Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
| | - Viktoriya Poterya
- J. Heyrovský Institute of Physical Chemistry, v.v.i., The Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
| | - Petr Slavíček
- University of Chemistry and Technology, 166 28 Prague 6, Czech Republic.
| | - Michal Fárník
- J. Heyrovský Institute of Physical Chemistry, v.v.i., The Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic.
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Vinklárek IS, Rakovský J, Poterya V, Fárník M. Different Dynamics of CH3 and Cl Fragments from Photodissociation of CH3Cl in Clusters. J Phys Chem A 2020; 124:7633-7643. [DOI: 10.1021/acs.jpca.0c05926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ivo S. Vinklárek
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
- Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 3121 16Prague 2Czech Republic
| | - Jozef Rakovský
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Viktoriya Poterya
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
| | - Michal Fárník
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 2155/3, 182 23 Prague 8, Czech Republic
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Reid M, Green V, Koehler SPK. Near-threshold photodissociation dynamics of CHCl3. Phys Chem Chem Phys 2014; 16:6068-74. [PMID: 24557156 DOI: 10.1039/c3cp55348e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Energy- and angle-resolved photofragment distributions for ground-state Cl ((2)P3/2) and spin-orbit excited Cl* ((2)P1/2) have been recorded using the velocity map imaging technique after photodissociation of chloroform at wavelengths of 193 and ∼235 nm. Translational energy distributions are rather broad and peak between 0.6 and 1.0 eV. The spin-orbit branching ratios [Cl*]/[Cl] are 1 and 0.3 at 193 and 235 nm, respectively, indicating the involvement of two or more excited state surfaces. Considering the anisotropy parameters and branching ratios collectively, we conclude that the reaction at 193 nm takes place predominantly on the (1)Q1 surface, while the (3)Q1 surface gains importance at lower dissociation energies around 235 nm.
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Affiliation(s)
- Mike Reid
- School of Chemistry, The University of Manchester, Manchester M13 9PL, UK.
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Affiliation(s)
- Dave Townsend
- Department of Chemistry, SUNY Stony Brook, Stony Brook, New York 11794, Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, and Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - Suk Kyoung Lee
- Department of Chemistry, SUNY Stony Brook, Stony Brook, New York 11794, Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, and Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - Arthur G. Suits
- Department of Chemistry, SUNY Stony Brook, Stony Brook, New York 11794, Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, and Department of Chemistry, Wayne State University, Detroit, Michigan 48202
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Lin JJ, Chen Y, Lee YY, Lee YT, Yang X. Photodissociation dynamics of CH3Cl at 157.6 nm: Evidence for CH2(X̃3B1/ã1A1)+HCl product channels. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00979-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Dorfman G, Melchior A, Rosenwaks S, Bar I. Vibrationally Mediated Photodissociation of Jet-Cooled CH3CF2Cl: A Probe of Energy Flow and Bond Breaking Dynamics. J Phys Chem A 2002. [DOI: 10.1021/jp014431v] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gabriela Dorfman
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Aviva Melchior
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Salman Rosenwaks
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Ilana Bar
- The Institutes for Applied Research, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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Tao C, Dagdigian PJ. Vibrationally mediated photodissociation of CH3Cl: the v=3 and 4 CH stretch overtone levels. Chem Phys Lett 2001. [DOI: 10.1016/s0009-2614(01)01263-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Bar I, Rosenwaks S. Controlling bond cleavage and probing intramolecular dynamics via photodissociation of rovibrationally excited molecules. INT REV PHYS CHEM 2001. [DOI: 10.1080/01442350110076484] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Melchior A, Chen X, Bar I, Rosenwaks S. Photolysis and Spectroscopy of Vibrationally Excited C−H Overtones of CHFCl2. J Phys Chem A 2000. [DOI: 10.1021/jp000791r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aviva Melchior
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Xiangling Chen
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Ilana Bar
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | - Salman Rosenwaks
- Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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Melchior A, Chen X, Bar I, Rosenwaks S. Vibrationally excited states of CH3CFCl2: Intramolecular vibrational redistribution and photodissociation dynamics. J Chem Phys 2000. [DOI: 10.1063/1.481752] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Melchior A, Chen X, Bar I, Rosenwaks S. Alteration of Cl spin–orbit branching ratios via photodissociation of pre-excited fundamental CH3 stretch of CH3CFCl2. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)01232-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Barnes RJ, Sinha A, Dagdigian PJ, Lambert HM. Doppler line shapes in the photolysis of laser excited, aligned molecules: Application to the vibrationally mediated photodissociation of HN3. J Chem Phys 1999. [DOI: 10.1063/1.479261] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Lambert HM, Dagdigian PJ. Photodissociation of CH stretch overtone excited CH3Cl and CHD2Cl(vCH=5): Cl spin–orbit branching and atomic fragment yields. J Chem Phys 1998. [DOI: 10.1063/1.477427] [Citation(s) in RCA: 30] [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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