Term: photon flow, \(\mathit{\Phi} _{\text{p}}\)
https://doi.org/10.1351/goldbook.P04633

Definition:
The number of photons (quanta, N) per unit time. (dN/dt, simplified expression: Φ p = N t when the number of photons is constant over the time considered). The SI unit is s-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.

Related Terms:
1) radiant power (http://doi.org/10.1351/goldbook.R05046).
2) einstein (http://doi.org/10.1351/goldbook.E01914).
3) spectral photon flow (http://doi.org/10.1351/goldbook.S05820).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2263 (https://doi.org/10.1351/pac199668122223)

Citation: 'photon flow, \(\mathit{\Phi} _{\text{p}}\)' 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.P04633

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