Theoretical study on the mechanism of the reaction of CH3CF2O2 with HO2 radical

Density functional theory (DFT) B3LYP method was employed to study the mechanism of the reaction of CH3CF2O2 radical and HO2 radical at the 6-311G,6-311+G(d),6-311++G(d, p) levels. The results indicate that there are two reaction pathways in this reaction. The main reaction pathway is CH3CF2O2 +HO2 -> IM1 -> TS1 -> CH3CF2OOH +O-2, the corresponding activation energy is 77.21 kJ center dot mol(-1), and the main products are O-2 and CH3CF2OOH. They are in good agreement with the experimental results. The other reaction pathway is CH3CF2O2+HO2 -> IM2 -> TS2 -> IM3 -> TS3 -> IM4+ IM5 -> IM4+ TS4 -> IM4+OH+O-2 -> TS5+OH+O-2 -> CH3+ CF2O+OH+O-2 -> CH3OH+CF2O+O-2, and the corresponding activation energy is 93.42 kJ center dot mol(-1). The results show that this reaction pathway can also occur, and it is in agreement with the results in literatures.