| Research Abstract |
The reactive processes of metastable molecular nitrogen were investigated.N_2(a^1Πg) was produced by laser two-photon excitation of ground-state molecular nitrogen.The near-by N_2(a'^1Σu)state can be produced by collisional relaxation of this N_2(a)state.H(D) atoms were identified by a two-photon laser-induced fluorescence technique as products of these metastable nitrogen molecules with some simple hydride(deuteride)compounds.The following results were obtained.(1)N_2(a')can be deactivated efficiently by hydrogen, methane, and water molecules and the production of H atoms is one of the major exit channels.(2)In the reaction of N_2(a') with CH_2D_2 and HOD, the yields of H and D atoms are the same, implying that, the reaction proceeds via intermediate complexes.(3)O_2 and Xe deactivate N_2(a')efficiently to produce triplet-state molecular nitrogen, while such intersystem crossing is inefficient in the collisional processes with N_2 and Ar.In addition to these, it was revealed that N_2(B^3Πg)and N_2(W^3Δu)states are produced selectively in the energy transfer from Xe(6s[3/2]_1) to N_2(X ^1Σg^+).The rate constants for the overall quenching of N_2(B^3 Πg, υ=0)are one order of magnitude smaller than those for the quenching of N_2(B^3 Πg, υ≧1). By choosing the amount of H(D) atoms produced in the reaction of Xe(6s[3/2]_1,) with H_2(D_2) as a standard, it was revealed that the production of H(D) atoms is one of the most important exit channels in the reaction of N_2(B^3 Πg, υ=0) with H_2(D_2), while the relaxation to N_2(A)is minor.These results are important not only in the field of basic science but also in the applied fields such as plasma technology.
|
