Term: spectral photon flow, \(\varPhi_{\text{p}\lambda}\)
https://doi.org/10.1351/goldbook.S05820

Definition:
The photon flow, Φ p, at wavelength λ per unit wavelength interval. The SI unit is s-1 m-1, but a commonly used unit is s-1 nm-1. Alternatively, the term can be used with the amount of photons (mol or its equivalent einstein), the SI unit then being mol s-1 m-1 and the common unit mol s-1 nm-1.

Related Terms:
1) photon flow (http://doi.org/10.1351/goldbook.P04633).
2) wavelength (http://doi.org/10.1351/goldbook.W06659).
3) einstein (http://doi.org/10.1351/goldbook.E01914).

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

Citation: 'spectral photon flow, \(\varPhi_{\text{p}\lambda}\)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S05820

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