Reaction rates of the reactions of OH(X [formula omitted]) with NH(a [formula omitted]) and HN 3(X̃)

Abstract

The rate constants of the radical–radical reaction OH(X 2 Π )+NH(a 1 Δ )→products and the radical–molecule reaction OH(X 2 Π )+HN 3→products were determined in a quasistatic laser photolysis cell at room temperature and a total pressure of 20 mbar. The radicals OH(X 2 Π ) and NH(a 1 Δ ) were generated by exciplex laser photolysis of H 2O 2 and HN 3, respectively and detected by laser-induced fluorescence. The fluorescence time profiles of these radicals were monitored at variable delay times between photolysis and detection pulses and thus time resolution was obtained. The measurements yielded the rate constants k 1=(7.0±2)×10 14 cm 3 mol −1 s −1 and k 2=(7.7±1)×10 11 cm 3 mol −1 s −1.