relation: http://publicatio.bibl.u-szeged.hu/24762/ title: Benchmark Ab Initio Characterization of the Abstraction and Substitution Pathways of the Cl + CH3CN Reaction creator: Tóth Petra creator: Szűcs Tímea creator: Czakó Gábor subject: 01.04.03. Fizikai kémia, polimertudomány, elektrokémia (szárazelemek, akkumulátorok, üzemanyagcellák, fémek korróziója, elektrolízis) description: We investigate the reaction pathways of the Cl + CH3CN system: hydrogen abstraction, methyl substitution, hydrogen substitution, and cyanide substitution, leading to HCl + CH2CN, ClCN/CNCl + CH3, ClCH2CN + H, and CH3Cl + CN, respectively. Hydrogen abstraction is exothermic and has a low barrier, whereas the other channels are endothermic with high barriers. The latter two can proceed via a Walden inversion or front-side attack mechanism, and the front-side attack barriers are always higher. The C-side methyl substitution has a lower barrier and also a lower endothermicity than the N-side reaction. The computations utilize an accurate composite ab initio approach and the explicitly correlated CCSD(T)-F12b method. The benchmark classical and vibrationally adiabatic energies of the stationary points are determined with the most accurate CCSD(T)-F12b/aug-cc-pVQZ energies adding further contributions of the post-(T) and core correlation, scalar relativistic effects, spin-orbit coupling, and zero-point energy corrections. These contributions are found to be non-negligible to reach subchemical accuracy. © date: 2022 type: Folyóiratcikk type: PeerReviewed format: text identifier: http://publicatio.bibl.u-szeged.hu/24762/1/JPCA_126_2802_2022.pdf identifier: Tóth Petra; Szűcs Tímea; Czakó Gábor: Benchmark Ab Initio Characterization of the Abstraction and Substitution Pathways of the Cl + CH3CN Reaction. JOURNAL OF PHYSICAL CHEMISTRY A, 126 (18). pp. 2802-2810. ISSN 1089-5639 (2022) identifier: doi:10.1021/acs.jpca.2c01376 relation: http://doi.org/10.1021/acs.jpca.2c01376 relation: 32895238 language: eng relation: info:eu-repo/semantics/altIdentifier/doi/10.1021/acs.jpca.2c01376 rights: info:eu-repo/semantics/openAccess