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Electron-Impact Total Ionization Cross Sections of Molecular Ions



Yong Sik Kim, Karl Irikura, M A. Ali


The Binary-Encounter-Bethe (BEB) model for electron-impact total ionization cross sections of neutral molecules has been modified for molecular ions. The total ionization cross section 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.
Journal of Research (NIST JRES) -
105 No. 2


electron-impact ionization, molecular ion, total ionization cross sections


Kim, Y. , Irikura, K. and Ali, M. (2000), Electron-Impact Total Ionization Cross Sections of Molecular Ions, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 30, 2024)


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Created February 29, 2000, Updated October 12, 2021