Title: X-ray absorption analysis
Long Title: IUPAC Gold Book - X-ray absorption analysis
DOI: 10.1351/goldbook.08766
Status: current

Definition
Measurement principle of X-ray analysis in which the absorption spectrum is used to measure the number of atoms, species, and other parameters of chemical elements.

Notes
1) XAS measures changes in the linear absorption coefficient of an element in a sample as a function of incident photon energy.
2) XAS requires a highly monochromatic (with \(\Delta E/E \approx \pu{E-4}\) to \(\pu{E-5}\)), high flux X-ray beam.

Related Terms
- X-ray absorption near edge structure: https://goldbook.iupac.org/terms/view/08768
- X-ray analysis: https://goldbook.iupac.org/terms/view/08769

Source
- PAC, 2021, 93, 69. 'Vocabulary of radioanalytical methods (IUPAC Recommendations 2020)' on page 105 (https://doi.org/10.1515/pac-2019-0302)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08766/html
- json: https://goldbook.iupac.org/terms/view/08766/json
- xml: https://goldbook.iupac.org/terms/view/08766/xml

Citation: Citation: 'X-ray absorption analysis' 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.08766
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Accessed: 2026-06-28T21:45:34+00:00