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Rhyman L, Lee EPF, Ramasami P, Dyke JM. A study of the thermodynamics and mechanisms of the atmospherically relevant reaction dimethyl sulphide (DMS) with atomic chlorine (Cl) in the absence and presence of water, using electronic structure methods. Phys Chem Chem Phys 2023; 25:4780-4793. [PMID: 36692209 DOI: 10.1039/d2cp05814f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The thermodynamics and mechanisms of the atmospherically relevant reaction dimethyl sulphide (DMS) + atomic chlorine (Cl) were investigated in the absence and presence of a single water molecule, using electronic structure methods. Stationary points on each reaction surface were located using density functional theory (DFT) with the M06-2X functional with aug-cc-pVDZ (aVDZ) and aug-cc-pVTZ (aVTZ) basis sets. Then fixed point calculations were carried out using the UM06-2X/aVTZ optimised stationary point geometries, with aug-cc-pVnZ basis sets (n = T and Q), using the coupled cluster method [CCSD(T)], as well as the domain-based local pair natural orbitals coupled cluster [DLPNO-UCCSD(T)] approach. Four reaction channels are possible, formation of (A) CH3SCH2 + HCl, (B) CH3S + CH3Cl, (C) CH3SCl + CH3, and (C') CH3S(Cl)CH3. The results show that, in the absence of water, channels A and C' are the dominant channels. In the presence of water, the calculations show that the reaction mechanisms for A and C formation change significantly. Channel A occurs via submerged TSs and is expected to be rapid. Channel B occurs via TSs which present significant energy barriers indicating that this channel is not significant in the presence of water relative to CH3SCH2 + HCl and DMS·Cl adduct formation, as is the case in the absence of water. Channel C was not considered as it is endothermic in the absence of water. In the presence of water, pathways which proceed via (a) DMS·H2O + Cl, (b) Cl·H2O + DMS and (c) DMS·Cl + H2O were considered. It was found that under tropospheric conditions, reactions via pathway (b) are of minor importance relative to those that proceed via pathways (a) and (c). This study has shown that water changes the mechanisms of the DMS + Cl reactions significantly but the presence of water is not expected to affect the overall reaction rate coefficient under atmospheric conditions as the DMS + Cl reaction has a rate coefficient at room temperature close to the collisional limit.
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Affiliation(s)
- Lydia Rhyman
- Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit, 80837, Mauritius. .,Centre For Natural Product Research, Department of Chemical Sciences, University of Johannesburg, Doornfontein, Johannesburg, 2028, South Africa
| | - Edmond P F Lee
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
| | - Ponnadurai Ramasami
- Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit, 80837, Mauritius. .,Centre For Natural Product Research, Department of Chemical Sciences, University of Johannesburg, Doornfontein, Johannesburg, 2028, South Africa
| | - John M Dyke
- School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK.
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Young NA. Main group coordination chemistry at low temperatures: A review of matrix isolated Group 12 to Group 18 complexes. Coord Chem Rev 2013. [DOI: 10.1016/j.ccr.2012.10.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rodríguez Pirani LS, Erben MF, Della Védova CO. The ionic nature of methylsulfur trichloride species. INORG CHEM COMMUN 2012. [DOI: 10.1016/j.inoche.2012.09.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Rhyman L, Armata N, Ramasami P, Dyke JM. A Study of the Atmospherically Important Reactions between Dimethyl Selenide (DMSe) and Molecular Halogens (X2 = Cl2, Br2, and I2) with ab initio Calculations. J Phys Chem A 2012; 116:5595-603. [DOI: 10.1021/jp302750a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lydia Rhyman
- Computational Chemistry Group,
Department of Chemistry, University of Mauritius, Réduit, Mauritius
| | - Nerina Armata
- School of Chemistry, University of Southampton, Southampton, UK SO17 1BJ
| | - Ponnadurai Ramasami
- Computational Chemistry Group,
Department of Chemistry, University of Mauritius, Réduit, Mauritius
| | - John M. Dyke
- School of Chemistry, University of Southampton, Southampton, UK SO17 1BJ
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Beccaceci S, Armata N, Ogden JS, Dyke JM, Rhyman L, Ramasami P. A study of the atmospherically important reactions of dimethylsulfide (DMS) with I2 and ICl using infrared matrix isolation spectroscopy and electronic structure calculations. Phys Chem Chem Phys 2012; 14:2399-407. [DOI: 10.1039/c2cp23392d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Dyke J. Photoionization Studies of Reactive Intermediates of Importance in the Atmosphere. CHEMISTRY FOR SUSTAINABLE DEVELOPMENT 2012. [DOI: 10.1007/978-90-481-8650-1_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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