THEORETICAL STUDY OF MECHANISM FOR THE ATMOSPHERIC REACTION CF3CHFO2 + NO

Abstract

The mechanism of the reaction CF3CHFO2 + NO was investigated using ab initio and density functional theory (DFT). The optimized geometries for all stationary points on the reaction energy surface were calculated using MP2 and B3LYP methods with the aug-cc-pVDZ basis set. Single-point energy calculations were performed using the coupled cluster method with single, double and perturbative triple configurations, CCSD(T). The most important energy minima on the potential energy surface (PES) were found corresponding to two conformers of the peroxynitrite association adducts, cis- CF3CHFOONO and trans- CF3CHFOONO , and the nitrate, CF3CHFONO2 . The radical pairs ( CF3CHFO + NO2 ) and the nitrate are formed through the breaking of the peroxy bond of trans- CF3CHFOONO and the rearrangement of cis- CF3CHFOONO , respectively. The nitrate can be decomposed to carbonylated species ( CF3CHO or CF3CFO ), nitryl fluoride (NO2F), nitrous acid (HONO), and radical pairs ( CF3CHFO + NO2 ), which are of potential atmospheric importance.