Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Electron-Impact Total Ionization Cross-Sections of the Chlorofluoromethanes



Karl K. Irikura, M A. Ali, Yong Sik Kim


Electron-impact total ionization cross sections for CCl3F (Freon 11), CCl2F2 (Freon 12), CClF3 (Freon 13), CHCl2F (Freon 21), CHClF2 (Freon 22), and CH2ClF (Freon 31) are calculated using the Binary-Encounter-Bethe (BEB) theoretical model. The BEB model requires only binding energies and kinetic energies of molecular orbitals, as computed using standard molecular orbital program packages. Experimental cross sections, where available, agree with the BEB results. All-electron ab initio calculations yield slightly larger BEB cross-sections than than do pseudopotential calculations.
International Journal of Mass Spectrometry
No. 1-3


ab initio, chlorofluorocarbon, cross section, Freon, ionization, quantum chemistry


Irikura, K. , Ali, M. and , Y. (2003), Electron-Impact Total Ionization Cross-Sections of the Chlorofluoromethanes, International Journal of Mass Spectrometry (Accessed June 18, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created January 1, 2003, Updated February 17, 2017