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Theory for Ionization of Molecules by Electrons



Yong Sik Kim, M E. Rudd


A simple yet effective theory for the total ionization cross sections of molecules by electron impact is described. The theory, called the Binary Encounter Bethe [BEB] model, combines a modified form of the Mott cross section for low incident energies T and the dipole interaction part of the Bethe theory for high T. The BEB model has been applied to a large variety of molecules and their fragments, and was found to reproduce known cross sections from thresholds to several keV in T within 5-15% at the peak. The BEB model uses simple input data, which are available from standard molecular wave function codes, and provides analytic expressions for the ionization cross sections convenient for many applications.
Atomic and Molecular Physics
No. 4


electron-impact ionization, electron-molecule collision


, Y. and Rudd, M. (1999), Theory for Ionization of Molecules by Electrons, Atomic and Molecular Physics (Accessed June 21, 2024)


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Created March 1, 1999, Updated February 17, 2017