Term: secular equation
https://doi.org/10.1351/goldbook.ST07098

Definition:
In molecular orbital theory, the determinant of matrix elements whose solution leads to the set of energy levels of molecular orbitals for a given system.

Related Terms:
1) molecular orbital (http://doi.org/10.1351/goldbook.M03996).

Source: PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1962 (https://doi.org/10.1351/pac199971101919)

Citation: 'secular equation' 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.ST07098

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