Term: excess Rayleigh ratio
https://doi.org/10.1351/goldbook.E02236

Definition:
The difference between the Rayleigh ratio for a dilute solution and for pure solvent. If the scattering intensity is not reduced to the Rayleigh ratio, the difference between the scattering intensities for a dilute solution and that for pure solvent is named 'excess scattering'.

Related Terms:
1) rayleigh ratio (http://doi.org/10.1351/goldbook.R05159).
2) dilute solution (http://doi.org/10.1351/goldbook.D01739).
3) scattering (http://doi.org/10.1351/goldbook.S05487).

Source: Purple Book, 1st ed., p. 66 (http://old.iupac.org/publications/books/author/metanomski.html)

Citation: 'excess Rayleigh ratio' 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.E02236

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