Charge-transfer rate constants for N2+(ν = 0–4) with Ar at thermal energies

Rate constants for the charge-transfer reaction N2+(ν) + Ar → N2 + Ar+ are measured at thermal energies as a function of initial vibrational excitation by laser-induced fluorescence. The reaction is slow for ν = 0, whereas the rate constants for ν = 1–4 are large (≈ 0.5 Langevin rate) and show little dependence on the vibrational level. The rate constants are quantitatively described by a simple model based on energy resonance and a set of modified Frank-Condon factors, which take into account the change in vibrational wave functions of N2+ and N2 at short (N2Ar)+ distances.