Direct double ionization for molecules of H₂ and N₂ induced by electron-impact

The direct double ionization of H2 and N2 molecules induced by electron-impact are investigated theoretically. Our theoretical calculation combines the binary-encounter-Bethe theory employed for molecular electron-impact single ionization and knock-out mechanism derived from the many-body perturbation theory. The process of electron-impact direct double ionization for molecules in our consideration is treated as the coupling of primary single ionization and knock-out process. The knock-out process is constituted by all the possible secondary single ionization processes. There is a good agreement between our theoretical results and available experimental measurements both for the molecules of H2 and N2. Our approach can obtain the cross section of each ionization channel, which is helpful to understanding for ionization competition mechanism of small homo-nuclear diatomic molecules.(c) 2023 Elsevier B.V. All rights reserved.