Studies on the Reactions of CH (<i>v</i> = 0 and 1) with NO and O2

Abstract

Abstract Rate constants for the reactions of CH(X2Π : v = 0,1) with NO and O2 are measured under pseudo-first-order conditions at 297 ± 5 K. CH(X2Π : v = 0,1) radicals are generated by excimer laser photolysis of CHBr3 and (CH3)2 CO at 193 nm, and detected by the laser-induced fluorescence (LIF) technique. The overall rate constants obtained at the total pressure of 20 Torr Ar are: kNO(v = 0) = (1.6 ± 0.2) × 10−10, kNO(v = 1) = (1.3 ± 0.6) × 10−10, kO2(v = 0) = (3.5 ± 0.3) × 10−11, and kO2(v = 1) = (3.4 ± 0.8) × 10−11 (cm3 molecule−1 s−1). No apparent pressure dependence is indicated for the rate constants over the pressure range of 5—50 Torr Ar for CH + NO, and 5—30 Torr Ar for CH + O2 reactions, respectively. The reaction mechanisms are discussed based on the quantum mechanical calculations of the potential energy surfaces of CH + NO and CH + O2 systems.