Title: spectral photon flow
Long Title: IUPAC Gold Book - spectral photon flow
DOI: 10.1351/goldbook.S05820
Status: current
Index: quantity

Definition
The photon flow, \(\varPhi_{\rm{p}}\), at wavelength \(\lambda \) per unit wavelength interval. The SI unit is \(\rm{s}^{-1}\ \rm{m}^{-1}\), but a commonly used unit is \(\rm{s}^{-1}\ \rm{nm}^{-1}\). Alternatively, the term can be used with the amount of photons (mol or its equivalent einstein), the SI unit then being \(\pu{mol s-1 m-1}\) and the common unit \(\pu{mol s-1 nm-1}\).

Related Terms
- einstein: https://goldbook.iupac.org//terms/view/E01914
- photon flow: https://goldbook.iupac.org//terms/view/P04633
- wavelength: https://goldbook.iupac.org//terms/view/W06659

Source
- PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2275 (https://doi.org/10.1351/pac199668122223)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/S05820/html
- json: https://goldbook.iupac.org/terms/view/S05820/json
- xml: https://goldbook.iupac.org/terms/view/S05820/xml

Citation: Citation: 'spectral photon flow' 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.S05820
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Accessed: 2026-06-06T21:29:13+00:00