Title: chain stiffness
Long Title: IUPAC Gold Book - chain stiffness
DOI: 10.1351/goldbook.12209
Status: current

Definition
Parameter describing the end-to-end distance of a linear, single-strand macromolecular chain having unperturbed dimensions relative to that of a model macromolecular chain not subject to short-range interactions.

Note
The steric factor, \(\sigma\), Kuhn segment length, \(l^{\prime}\), and persistence length, \(a\), are all measures of chain stiffness.

Related Term
- Kuhn segment length: https://goldbook.iupac.org//terms/view/12205

Source
- PAC, 2015, 87, 71. 'Definitions of terms relating to individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers (IUPAC Recommendations 2014)' on page 80 (https://doi.org/10.1515/pac-2013-0201)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12209/html
- json: https://goldbook.iupac.org/terms/view/12209/json
- xml: https://goldbook.iupac.org/terms/view/12209/xml

Citation: Citation: 'chain stiffness' 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.12209
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Accessed: 2026-07-14T06:51:43+00:00