Electron-impact total ionization cross sections of molecular ions

Abstract

The Binary-Encounter-Bethe (BEB) model for electron-impact total ionization cross sections of neutral molecules has been modified for molecular positive ions. The total ionization cross sections for H+2 , N+2 , CD+, and CO+ from the modified BEB formula are compared to available experimental data. The theory is in good agreement with experimental data on H+2 , N+2, and CD+, but the experimental data by Belic et al. on N+2 , and CO+ are lower than the theory. The large difference between the theory and experiment on CO+ is a strong indication of the dominance of the dissociative ionization channel, CO+C++O+, which was not included in the experiment.