Title: Auger parameter
Long Title: IUPAC Gold Book - Auger parameter
DOI: 10.1351/goldbook.09308
Status: current

Definition
Kinetic energy of a narrow Auger electron peak in a spectrum minus the kinetic energy of the most intense X-ray photoelectron peak from the same element.

Notes
1) The value of the Auger parameter depends on the energy of the X-rays, which therefore needs to be specified.
2) The Auger parameter is sometimes called the final state Auger parameter (see initial state Auger parameter).
3) The Auger parameter is useful for separating chemical states for samples in which charging causes uncertainty in the binding energy measurement or in which the binding energy shift is inadequate to identify the chemical state.
4) The Auger parameter is useful for evaluating the relaxation energy of the ionized matrix atom associated with the generation of a core hole for those Auger transitions between core levels, which have similar chemical shifts.

Related Terms
- initial state Auger parameter: https://goldbook.iupac.org//terms/view/09339
- modified Auger parameter: https://goldbook.iupac.org//terms/view/09343
- relaxation energy: https://goldbook.iupac.org//terms/view/09350

Source
- PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1820 (https://doi.org/10.1515/pac-2019-0404)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09308/html
- json: https://goldbook.iupac.org/terms/view/09308/json
- xml: https://goldbook.iupac.org/terms/view/09308/xml

Citation: Citation: 'Auger parameter' 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.09308
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Accessed: 2026-05-12T15:16:43+00:00