Title: critical excitation energy
Long Title: IUPAC Gold Book - critical excitation energy
DOI: 10.1351/goldbook.C01394
Status: current
Index: quantity

Definition
Minimum energy to excite a specific analytical signal. The term is most frequently used in connection with the generation of X-ray spectra, designating the ionization (binding) energy of the orbital on which the transition ends.

Related Term
- ionization (binding) energy: https://goldbook.iupac.org//terms/view/I03199

Source
- PAC, 1983, 55, 2023. 'Nomenclature, symbols and units recommended for in situ microanalysis (Provisional)' on page 2027 (https://doi.org/10.1351/pac198355122023)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01394/html
- json: https://goldbook.iupac.org/terms/view/C01394/json
- xml: https://goldbook.iupac.org/terms/view/C01394/xml

Citation: Citation: 'critical excitation energy' 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.C01394
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Accessed: 2026-04-27T14:55:53+00:00