Term: Guinier plot
https://doi.org/10.1351/goldbook.G02712

Definition:
A diagrammatic representation of data on scattering from large particles, obtained at different angles but at the same concentration, constructed by plotting log 10 Δ R θ or log 10 P θ versus (sin θ2)2 or q 2 and (usually) used for the evaluation of the radius of gyration. ΔRθ is the excess Rayleigh ratio, P θ the particle scattering function, θ the scattering angle and q the length of the scattering vector.

Related Terms:
1) scattering (http://doi.org/10.1351/goldbook.S05487).
2) radius of gyration (http://doi.org/10.1351/goldbook.R05121).
3) excess rayleigh ratio (http://doi.org/10.1351/goldbook.E02236).
4) particle scattering function (http://doi.org/10.1351/goldbook.P04429).
5) scattering angle (http://doi.org/10.1351/goldbook.S05488).
6) scattering vector (http://doi.org/10.1351/goldbook.S05494).

Source: Purple Book, 1st ed., p. 67 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'Guinier plot' 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.G02712

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