return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Comparisons > Ion > Compare Ionzation energy > Koopman IE for a few molecules

Koopmans' Theorem Comparison of Ionization Energy for a set of species

Select a species by entering a chemical formula.
or choose by chemical groups.

Rules for chemical formula

Species in the CCCBDB

A list of species that match the formula criteria is returned and one or more may be selected.

Going to the group selection page allows the selection of molecules with certain chemical groups, such as C=O bonds or NH2 groups. A list of species that match the group criteria is returned and one or more may be selected.

Caution! Choosing a long list may take a long time to to load. For example: 150 species takes about a minute.