Term: effectively infinite thickness
https://doi.org/10.1351/goldbook.E01895

Definition:
Solid or liquid samples of one gram or more are generally used in X-ray spectroscopy. If the sample is thick enough so that the intensity of characteristic fluorescent radiation is not significantly modified by an increase in thickness, the sample is described as a bulk sample of effectively infinite thickness.

Related Terms:
1) gram (http://doi.org/10.1351/goldbook.G02680).
2) x-ray spectroscopy (http://doi.org/10.1351/goldbook.X06718).
3) bulk sample (http://doi.org/10.1351/goldbook.B00756).

Source: Orange Book, 2nd ed., p. 182 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'effectively infinite thickness' 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.E01895

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