Title: internal valence force field
Long Title: IUPAC Gold Book - internal valence force field
DOI: 10.1351/goldbook.I03111
Status: current

Definition
A force field expressed in terms of bond-stretching, angle-bending, torsional and other displacements directly connected to the structural parameters of the molecule: \[V=\frac{1}{2}\ \sum k_{ij}\ R_{i}\ R_{j}\] or \[V=\frac{1}{2}\ \sum K_{ij}\ R_{i}\ R_{j}\] where \(k\) (or \(K\)) are the force constants and \(R\) the internal valence coordinates.

Related Terms
- angle: https://goldbook.iupac.org//terms/view/A00346
- force constants: https://goldbook.iupac.org//terms/view/F02481
- valence: https://goldbook.iupac.org//terms/view/V06588

Source
- PAC, 1978, 50, 1707. 'Definition and Symbolism of Molecular Force Constants' on page 1709 (https://doi.org/10.1351/pac197850111707)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/I03111/html
- json: https://goldbook.iupac.org/terms/view/I03111/json
- xml: https://goldbook.iupac.org/terms/view/I03111/xml

Citation: Citation: 'internal valence force 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.I03111
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Accessed: 2026-04-23T22:38:17+00:00