Title: molecular mechanics calculation
Long Title: IUPAC Gold Book - molecular mechanics calculation
DOI: 10.1351/goldbook.M03993
Status: current

Definition
An empirical calculational method intended to give estimates of structures and energies for conformations of molecules. The method is based on the assumption of 'natural' bond lengths and angles, deviation from which leads to strain, and the existence of torsional interactions and attractive and/or repulsive van der Waals and dipolar forces between non-bonded atoms. The method is also called '(empirical) force-field calculations'.

Related Terms
- conformations: https://goldbook.iupac.org/terms/view/C01258
- deviation: https://goldbook.iupac.org/terms/view/D01650
- strain: https://goldbook.iupac.org/terms/view/S06037
- van der Waals: https://goldbook.iupac.org/terms/view/V06597

Source
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1142 (https://doi.org/10.1351/pac199466051077)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/M03993/html
- json: https://goldbook.iupac.org/terms/view/M03993/json
- xml: https://goldbook.iupac.org/terms/view/M03993/xml

Citation: Citation: 'molecular mechanics calculation' 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.M03993
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Disclaimer: 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.
Accessed: 2026-05-10T20:42:42+00:00