Theoretical investigation on the mechanisms and kinetics of the reactions of hydroperoxy radical with dimethyl sulphide and ethyl methyl sulphide

An exhaustive and theoretical analysis for the CH3SCH3 + HOO• and CH3CH2SCH3 + HOO• reactions has been examined using quantum chemistry theory. The potential energy surface was obtained by the CCSD(T)/CBS//M06-2X/cc-pVTZ level of theory. The overall rate coefficients have been calculated and the energetics and reaction enthalpies are also calculated. The calculated kinetics demonstrate that the hydrogen abstraction channels from the -CH3 group in CH3SCH3 and the -CH2 group in CH3CH2SCH3 are major channels in the low temperature region (less than 1000 K). However, the CH3-transfer channels forming CH3OOH become competitive reaction channels with the increase in temperature.