New Insights into the Kinetics of the Reaction of Vinyl Radical with Nitrogen Dioxide

Abstract

The kinetics of the reactions of vinyl radical with NO2 have been investigated by theoretical calculations at the CCSD(T)-F12a/aVTZ-F12//M06-2X/aug-cc-pVDZ level. The μVT and RRKM/ME calculations were performed to obtain temperature- and pressure-dependent rate coefficients. The reaction starts with the vinyl radical attacking either the N-atom or O-atom of NO2, followed by several competing pathways, with the NO + CH2CHO product channel being the most favorable. Both barrier-less and the pathway via a saddle point for NO release were identified. The proposed pathways and rate coefficients were incorporated into a kinetic model, improving species evolution predictions in line with experiments.

Keywords: Vinyl radical, Nitrogen dioxide, Reaction mechanism, Ab initio, RRKM/Master Equation