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

Abstract

Abstract Quantum yields for the production of H(D) atoms in the reaction of singlet-excited metastable molecular nitrogen, N2(a 1 Π g, ν=0), with H2 and D2 were determined by analyzing the temporal profiles of N2(a, ν=0) and H(D)-atom densities after pulsed excitation. N2(a, ν=0) was produced by the two-photon excitation of ground-state N2, while H(D) atoms were detected by two-photon laser-induced fluorescence. N2(a, ν=0) was detected by laser-induced fluorescence utilizing the N2(b′ 1 Σ u+, ν=7) state as an upper-state. The H(D) atom yields are 0.5 ± 0.1 for H2 and 0.4 ± 0.1 for D2, suggesting that the near resonant relaxation to another metastable molecular nitrogen, N2(a′ 1 Σ u−), is also important. The production of N2(a′ 1 Σ u−) in collisions with H2(D2) was confirmed by measuring the H2(D2) pressure dependence of the two-photon laser-induced fluorescence signal of N2(a′ 1 Σ u−, ν=0) via the N2(b 1 Π u, ν=1) state.