Term: quantum mechanics/molecular mechanics (QM/MM)
https://doi.org/10.1351/goldbook.QT07469

Definition:
Hybrid procedure for the treatment of large molecular systems. A crucial part of the system (e.g., the chromophore and its surroundings) is treated explicitly by quantum mechanical (QM) techniques, whereas the rest of the system is approximated by a classical or molecular mechanics (MM) force field treatment.

Note: Sometimes called QC/MM.

Related Terms:
1) chromophore (http://doi.org/10.1351/goldbook.C01076).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 406 (https://doi.org/10.1351/pac200779030293)

Citation: 'quantum mechanics/molecular mechanics (QM/MM)' 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.QT07469

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