Reaction paths, kinetics and thermochemical properties on reaction of methylthiyl (CH3S)and methylthiomethyl (CH3SCH3) radicals with O2

摘要

Two association reaction systems, CH3S? + O2 and CH3SC?H2 + O2, are studied for theirthermochemical properties, reaction pathways and kinetics. We review the experimental andcomputational chemistry literature on these systems and use computational chemistry to furtherevaluate a number of reaction paths. CBS-QB3, G3MP2 and density functional methods areutilized to estimate ?Hf°298, S°298, and Cp°(T) for reactants, intermediate radicals, and transitionstates. Isodesmic working reactions are applied to evaluate enthalpies of formation.Intramolecular rotation potentials are calculated at the B3LYP/6-31G(d,p) level and used todetermine contributions to entropy and heat capacities. Kinetics parameters are evaluated usingchemical activation analysis and unimolecular dissociation of the stabilized adducts.