07343 IUPAC Gold Book - complete active space self-consistent field 10.1351/goldbook.CT07343 CT07343 current initialism: CASSCF 1 Computational scheme employed in multiconfigurational SCF theory especially suitable for studies of reactivity of excited states. The wavefunction is defined by selecting the set of active orbitals involved in the excitation or chemical reaction under investigation and is constructed as a linear expansion in the set of configuration functions that can be generated by occupying the active orbitals in all ways consistent with an overall spin and space symmetry (full configuration interaction, CI). configuration interaction, CI https://goldbook.iupac.org//terms/view/C01256 excited states https://goldbook.iupac.org//terms/view/E02257 multiconfigurational SCF theory https://goldbook.iupac.org//terms/view/MT07075 PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 315 (https://doi.org/10.1351/pac200779030293) https://goldbook.iupac.org/terms/view/CT07343/html https://goldbook.iupac.org/terms/view/CT07343/json https://goldbook.iupac.org/terms/view/CT07343/plain Citation: 'complete active space self-consistent field' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.CT07343 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-05-09T09:28:40+00:00