Term: spectral (photon) effectiveness
https://doi.org/10.1351/goldbook.S05814

Definition:
The reciprocal of the photon fluence rate, E p 0, at wavelength λ, causing identical photoresponse, Δ y, per unit time (Δ y Δ t). The effectiveness spectrum is directly proportional to the conversion spectrum of the sensory pigment, if spectral attenuance is negligible.

Related Terms:
1) photon fluence rate (http://doi.org/10.1351/goldbook.P04635).
2) wavelength (http://doi.org/10.1351/goldbook.W06659).
3) effectiveness (http://doi.org/10.1351/goldbook.E01897).
4) conversion spectrum (http://doi.org/10.1351/goldbook.C01319).
5) attenuance (http://doi.org/10.1351/goldbook.A00513).

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) effectiveness' 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.S05814

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