Computational study on the mechanisms and kinetics of the CH2CCl + O2 reaction

Abstract

The potential energy surface for the CH2CCl + O2 reaction has been investigated by using the CCSD(T)/cc-pVTZ//B3LYP/6-311++G(d,p) method. Two type reaction mechanisms have been located. The H-abstraction of CH2CCl by O2 generates CHCCl + HO2 surmounting a 20.86 kcal/mol barrier. The addition between O2 and CH2CCl proceeds to an intermediate CH2CClO2 (IM1t and IM1c) without a barrier, which can further dissociate or isomerize to various products with the complicated processes. The temperature and pressure dependence rate constants for the CH2CCl + O2 reaction were computed by means of multi-channel RRKM-TST theory. Moreover, TDDFT calculations imply that IM1t, IM1c, IM2, IM4, IM5t, and IM5c will photolyze under the sunlight.