Term: correlation energy
https://doi.org/10.1351/goldbook.C01349

Definition:
The difference between the Hartree–Fock energy calculated for a system and the exact non-relativistic energy of that system. The correlation energy arises from the approximate representation of the electron-electron repulsions in the Hartree–Fock method.

Related Terms:
1) hartree (http://doi.org/10.1351/goldbook.H02747).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2234 (https://doi.org/10.1351/pac199668122223)

Citation: 'correlation energy' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01349

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