Title: Stokes shift
Long Title: IUPAC Gold Book - Stokes shift
DOI: 10.1351/goldbook.S06031
Status: current

Definition
The difference (usually in frequency units) between the spectral positions of the band maxima (or the band origin) of the absorption and luminescence arising from the same electronic transition. Generally, the luminescence occurring at a longer wavelength than the absorption is stronger than the opposite. The latter may be called an anti-Stokes shift.

Related Terms
- coherent radiation: https://goldbook.iupac.org//terms/view/C01130
- luminescence: https://goldbook.iupac.org//terms/view/L03641
- wavelength: https://goldbook.iupac.org//terms/view/W06659

Source
- PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2278 (https://doi.org/10.1351/pac199668122223)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/S06031/html
- json: https://goldbook.iupac.org/terms/view/S06031/json
- xml: https://goldbook.iupac.org/terms/view/S06031/xml

Citation: Citation: 'Stokes shift' 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.S06031
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Accessed: 2026-04-18T16:32:58+00:00