Theoretical study of the reaction of ketenyl and nitrogen dioxide radicals (HCCO + NO2)

Portions of potential energy surface containing low-energy pathways of HCCO + NO2 reaction were constructed using the G3B3 method. These show that only two separate reaction pathways are possible leading to HCNO + CO2 and HCO + NO + CO. Selectivity between product channels (CO2 vs. CO) occurs very early on the attractive entrance channels. The absence of an entrance barrier is consistent with available rate constants showing their negative dependence on temperature. The product distribution estimated in this Letter is in agreement with recent experimental results of Meyer and Hershberger [J.P. Meyer, J.F. Hershberger, J. Phys. Chem. A, 109 (2005) 4772].