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Version History

Example of how to reference this online database:
Kim, Y.-K., Irikura, K.K., Rudd, M.E., Ali, M.A., Stone, P.M., Chang, J., Coursey, J.S., Dragoset, R.A., Kishore, A.R., Olsen, K.J., Sansonetti, A.M., Wiersma, G.G., Zucker, D.S., and Zucker, M.A. (2004), Electron-Impact Ionization Cross Section for Ionization and Excitation Database (version 3.0). [Online] Available: http://physics.nist.gov/ionxsec [2024, April 26]. National Institute of Standards and Technology, Gaithersburg, MD.

Citation Form:
Author/editor (Year), Title (edition). [Type of medium] Available: URL [Access date].

Version 3.0
August 2004
Electron-impact cross section data has been added for many molecules and atoms. Version 3.0 also includes a new graphical design and user interface, with the data for atoms and molecules accessed through different interfaces. Additions to the database include excitation cross sections for atoms H, He, & Li; and ionization cross sections for atoms B, C, N, O, Al, Ga, In; and for molecules C2H3, C3H3, C3H4 (allene & propyne), C3H5, C3H6, C4H2, C4H4, C4H6, C4H8 (1-butene, trans-2-butene & isobutene), C6H2, C6H6 (fulvene), SiF4, HO2, and six Freon molecules (CClF3, CCl2F2, CCl3F, CHClF2, CHCl2F, CH2ClF). The molecular orbital notation was modified for many of the molecules.
Version 2.1
November 2001
New theoretical data along with relevant references were added for the following hydrocarbon ions: H3O+, CH2+, CH3+, CH4+, C2H2+, C2H4+, and C2H6+.
Version 2.0
September 2000
New theoretical and experimental data along with relevant references were added for H2+, N2+, CO+, CH+, H2, He, NO2, BF, BF2, BF3, BCl, BCl2, BCl3, CF, CF2, CF3, CHO, CH2O, and C2H3O. Molecular orbital data (B, U, N, Q) for deep inner shells (mostly K shells) of molecules with heavy atoms have been added to all molecules.
Version 1.4
August 1998
One experimental data set was added for H2O.
Version 1.3
July 1998
Single Differential Cross Section data for H, He, and H2 were included. Data for halogen compounds were updated, and the graphing capabilities were expanded.
Version 1.2
January 1998
Data for halogen compounds were added, and additional internal changes were made.
Version 1.1
September 1997
Data for CH and C2H2 were added. Also added were BEB cross sections in tabular form for all atoms and molecules.
Version 1.0
August 1997
Original Release.


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