Ab initiomolecular dynamics investigation on the production Channels for the Reaction of O- with CH3F

Abstract

H-atom abstraction and H2O production channels for the reaction of O- with CH3F were reinvestigated using the ab initio molecular dynamics method at the B3LYP/6-31+G(d,p) level of theory and based on the Born- Oppenheimer approximation. The reactive trajectories were initiated at the transition state of H-atom abstraction. Thermal sampling at 300 K was chosen to determine the initial conditions. Additionally, the energies added to the transition vector of the barrier were restricted to 2.1, 36.8, and 62.8 kJ·mol -1, separately, to reveal the impact of different initial collision energies on the reaction pathways. The results of all the trajectory calculations demonstrate that the H-atom abstraction channel is the dominant production channel. Therefore, our calculations are consistent with previous experimental conclusions. Furthermore, the dynamic reaction pathways for H-atom abstraction and the H2O production channels on the exit-channel potential energy surface are described based on our calculations and thus a comprehensive reaction mechanismis revealed at the microscopic level. © Editorial office of Acta Physico-Chimica Sinica.