Term: Pariser–Parr–Pople (PPP) method
https://doi.org/10.1351/goldbook.PT07088

Definition:
A semi-empirical quantum mechanical method of calculation of the properties of conjugated molecules and ions from self-consistent-field theory and the π-electron approximation.

Source: PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1956 (https://doi.org/10.1351/pac199971101919)

Citation: 'Pariser–Parr–Pople (PPP) method' 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.PT07088

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