NH(A 3Π → X 3Σ −) Chemiluminescence from the CH(X 2 Π) + NO reaction

Abstract

NH(A 3Π → X 3Σ −) and OH(A 2Σ + → X 2Π) chemiluminescences from the reaction of CH(X 2Π) with NO and O 2, respectively, have been observed at room temperature. From the decay of such emissions we have measured the rate constants for these two reactions: k NO = (2.5 ± 0.5) × 10 −10 and k O2 = (8 ± 3) × 10 −11 cm 3 molecule −1 s −1, which are in agreement with previously reported rates determined by direct CH(X) detection using, laser-induced fluorescence. This indicates that a four-centered mechanism generating these excited species is operative in both reactions. The CH generation from 266 nm photolysis of CHBr 3 has also been investigated via analysis of CH* emissions.