Title: root-mean-square unperturbed radius of gyration
Long Title: IUPAC Gold Book - root-mean-square unperturbed radius of gyration
DOI: 10.1351/goldbook.12193
Status: current

Definition
Root-mean-square radius of gyration of a macromolecule having unperturbed dimensions.

Note
The traditionally used symbol \(\lt\!s^{2}\!\gt_{\rm{o}}^{1/2}\) is not recommended as it signifies the square root of the unperturbed average, namely, \(\lt \; \gt_{\rm{o}}^{1/2}\) of \(s^{2}\) rather than the root-mean-square, namely, \(\lt \; \gt^{1/2}\) of the unperturbed squared radius, \(s_{\rm{o}}^{2}\).

Related Term
- Root-mean-square radius of gyration: https://goldbook.iupac.org//terms/view/12191

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 75 (https://doi.org/10.1515/pac-2013-0201)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/12193/html
- json: https://goldbook.iupac.org/terms/view/12193/json
- xml: https://goldbook.iupac.org/terms/view/12193/xml

Citation: Citation: 'root-mean-square unperturbed radius of gyration' 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.12193
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Accessed: 2026-06-20T10:16:49+00:00