Term: steric factor
https://doi.org/10.1351/goldbook.S05999

Definition:
The ratio, σ, of the root-mean-square end-to-end distance of a polymer chain with unperturbed dimensions, < r2 >0(1/2), to that of a freely rotating chain with the same structure, < r2 >0,f(1/2), i.e. sqrt(< r2 >0/< r2 >0,f), in the limit of infinite chain length. The steric factor reflects the effect of hindrance to free rotation.

Related Terms:
1) root-mean-square end-to-end distance (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.R05405).
2) freely rotating chain (<em>in polymers</em>) (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.F02518).
3) chain length (<em>in polymers</em>) (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.C00956).
4) steric factor (<em>in polymers</em>) (<em>in polymers</em>) (http://doi.org/10.1351/goldbook.S05998).

Source: Purple Book, 1st ed., p. 50 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'steric factor' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S05999

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