Title: worm-like chain
Long Title: IUPAC Gold Book - worm-like chain
DOI: 10.1351/goldbook.W06692
Status: current

Definition
A hypothetical linear macromolecule consisting of an infinitely thin chain of continuous curvature; the direction of curvature at any point is random. The model describes the whole spectrum of chains with different degrees of chain stiffness from rigid rods to random coils, and is particularly useful for representing stiff chains. In the literature this chain is sometimes referred to as a Porod–Kratky chain. Synonymous with continuously curved chain.

Related Term
- linear macromolecule: https://goldbook.iupac.org/terms/view/L03554

Source
- Purple Book, 1st ed., p. 51 (http://old.iupac.org/publications/books/author/metanomski.html)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/W06692/html
- json: https://goldbook.iupac.org/terms/view/W06692/json
- xml: https://goldbook.iupac.org/terms/view/W06692/xml

Citation: Citation: 'worm-like chain' 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.W06692
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Accessed: 2026-06-28T08:00:09+00:00