Temperature Dependence of the Rate Constants of the Reaction O + NO + M → NO 2 + M (M = He, NO, N 2 , CH 4 )

Values of absolute rate constants of the termolecular reaction O + NO + M → NO 2 + M were determined for different third bodies (M = He, NO, N 2 , and CH 4 ) at temperatures ranging from 200 to 370 K, Small amounts of O atoms were generated in the H 2 ‐laser photolysis of NO and were monitored by NO   2 *chemiluminescent emission. The temperature dependence of the rate constants can be expressed by k 1,M = B x ( T/K ) −n with n = (1.10 ± 0.06) and B = 3.3 (+ 1.4; – 1.0) · 10 −29 cm 6 s ‐1 for M = He; n = (1.38 ± 0.06) and B = 3.3 (+ 1.2; – 0.9) · 10 −28 cm 6 s ‐1 for M = NO; n = (1.44 ± 0.10) and B = 3.2 ( + 2.5; – 1.4) · 10 −28 cm 6 s ‐1 for M = N 2 ; and n = (1.55 ± 0.15) and B = 7.9 ( + 10.7; – 4.6) · 10 −28 cm 6 s ‐1 for M = CH 4 . These results are discussed and compared with previous experimental and theoretical work.