Title: X-ray jump ratio
Long Title: IUPAC Gold Book - X-ray jump ratio
DOI: 10.1351/goldbook.09442
Status: current

Definition
X-ray absorption coefficient at an energy just above an absorption edge divided by that at an energy just below the edge.

Note
X-ray absorption spectra can have complex shapes for X-ray energies in the vicinity of photoionization thresholds, and a well-defined edge is not always observed at the threshold.

Source
- PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1850 (https://doi.org/10.1515/pac-2019-0404)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09442/html
- json: https://goldbook.iupac.org/terms/view/09442/json
- xml: https://goldbook.iupac.org/terms/view/09442/xml

Citation: Citation: 'X-ray jump ratio' 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.09442
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Accessed: 2026-05-18T05:30:00+00:00