Product Branching Ratios of the CH + NO Reaction

The multichannel CH + NO reaction was studied, at room temperature, in a low-pressure fast-flow reactor. CH was obtained from the reaction of CHBr 3 with potassium atoms. The overall rate constant was found to be (1.9 ± 0.5) × 10 -10 cm 3 molecule -1 s -1 . The relative branching ratios of NH(A 3 Π) + CO and NCO(A 2 Σ + ) + H chemiluminescent pathways were determined as 42% and 58% (±7). Nascent NH(A 3 Π) was distributed between the vibrational levels v ‘ = 1 and v ‘ = 0 in the proportion of 33% and 67% (±3%). The CN chemiluminescence from the energetically allowed CN(A 2 Π i ) + OH pathway could not be detected. Also, CN(X 2 Σ + ) could not be detected by laser-induced fluorescence. Relative product branching ratios were determined over the channels yielding atoms probed by resonance fluorescence in the vacuum ultraviolet: O + HCN, (72 ± 10)%; H + NCO, (21 ± 10)%; N + HCO, (7 ± 3)%.