Title: force constants
Long Title: IUPAC Gold Book - force constants
DOI: 10.1351/goldbook.F02481
Status: current

Definition
The coefficients in an expansion of the intramolecular potential function in terms of a definite set of coordinates, the values of which define the deformation of the molecule away from its equilibrium configuration. In order to define force constants, one has to indicate both the definition of each coordinate and the expansion of the potential.

Related Term
- intramolecular: https://goldbook.iupac.org//terms/view/I03130

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/F02481/html
- json: https://goldbook.iupac.org/terms/view/F02481/json
- xml: https://goldbook.iupac.org/terms/view/F02481/xml

Citation: Citation: 'force constants' 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.F02481
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Accessed: 2026-04-23T23:44:26+00:00