Production yields of H(D) atoms in the reaction of N2(a 1Πg, v=0) with H2 and D2

Quantum yields for the production of H(D) atoms in the reaction of singlet-excited metastable molecular nitrogen, N-2(a (1)Pig, v = 0), with H-2 and D-2 were determined by analyzing the temporal profiles of N-2(a, v = 0) and H(D)-atom densities after pulsed excitation. N-2(a. v = 0) was produced by the two-photon excitation of ground-state N-2 while H(D) atoms were detected by twophoton laser-induced fluorescence. N-2(a, v = 0) was detected by laser-induced fluorescence utilizing the N-2(b' (1)Sigmau(+), v = 7) state as an upper-state. The H(D) atom yields are 0.5 +/- 0.1 for H-2 and 0.4 +/- 0.1 for D-2, suggesting that the near resonant relaxation to another metastable molecular nitrogen, N-2(a' 1Sigmau(-)), is also important. The production of N-2(a' (1)Sigmau(-)) in collisions with H-2(D-2) was confirmed by measuring the H-2(D-2) pressure dependence of the two-photon laser-induced fluorescence signal of N-2(a' (1)Sigmau(-), v = 0) via the N-2 (b 1Piu, v = 1) state. (C) 2004 Elsevier B.V. All rights reserved.