Kinetics of the self-reaction and the reaction with OH of the amidogen radical

The kinetics of the self-reaction and the reaction with OH of the amidogen radical were studied at 298 K by pulse radiolysis combined with UV detection of NH2 and OH radicals at 597.7 and 309.0 nm. The rate constant for the association reaction of NH2 radicals was found to be pressure dependent in the range 200–1000 mbar of SF6, and by Troeʹs analysis the following high- and low-pressure limiting rate constants were obtained: κrec, ∞(7.1 ± .8) × 1010(T/300)0.27M−1s−1 and κrec, 0/[SF6]=(7.1 ± 1.5) × 1012(T/300)−3.9M−2s−1 in the temperature range 200–400 K. For the reaction between NH2 and OH radicals no pressure dependence was observed in the range 500–1000 mbar SF6, and the following high-pressure limiting rate constant was derived: (5.6 ± 1.0) × 1010(T/300)0.20M−1s−1 in the temperature range 200–400 K.