Electron transfer and excitation in low energy N+2–alkali atom collisions

Abstract

Inelastic collisions between N⁺₂ ions and alkali atoms Li, K) have been investigated in the kinetic energy range 50–1000 eV (lab) using a crossed beam apparatus and spectroscopic analysis of collision‐produced radiation (180–850 nm). Collision‐induced excitation to the lowest alkali atom excited state was observed to compete favorably with near resonant charge transfer to N₂(C). The vibrational state distributions within N₂(C) from N⁺₂–K collisions are in accord with a vertical transition model, while the distributions resulting from N⁺₂–Li and Na collisions are not. These results are discussed within the framework of a surface crossing model developed to describe such collisions. Absolute cross sections for the observed processes are also reported.