Reaction rates of the reactions of OH(X-2 Pi) with NH(a(1)Delta) and HN3((X)over-tilde)

The rate constants of the radical-radical reaction OH(X(2)Pi) + NH(a (1)Del ta) --> products and the radical-molecule reaction OH(X (2)Pi) + HN3 --> pr oducts were determined in a quasistatic laser photolysis cell at room tempe rature and a total pressure of 20 mbar. The radicals OH(X(2)Pi) and NH(a(1) Delta) were generated by exciplex laser photolysis of H2O2 and HN3, respect ively and detected by laser-induced fluorescence. The fluorescence time pro files of these radicals were monitored at variable delay times between phot olysis and detection pulses and thus time resolution was obtained, The meas urements yielded the rate constants k(1) = (7.0 +/- 2) x 10(14) cm(3) mol(- 1) s(-1) and k(2) = (7.7 +/- 1) x 10(11) cm(3) mol(-1) s(-1). (C) 1999 Else vier Science B.V. All rights reserved.