Laser induced fluorescence studies of the charge transfer reactions of N2+ with Ar and N2

Abstract

The charge transfer reactions of N₂⁺ with Ar and N₂ have been studied using laser induced fluorescence to monitor N₂⁺. The ions were formed initially within a quadrupole ion trap by electron impact of neutral N₂. The experimental conditions were varied such that the trapped N₂⁺ could be examined under collision free conditions or after experiencing a controlled number of collisions with selected background gas. The ion–molecule collisions rapidly altered the internal energy distribution of the trapped N₂⁺ and by monitoring these changes charge transfer cross sections for individual initial vibrational states of the N₂⁺ with Ar and N₂ have been estimated. The results show a strong vibrational dependence of the charge transfer cross section in the N₂⁺–N₂ system and no measureable dependence in the N₂⁺–Ar system.