14059 IUPAC Gold Book - photonic yield spectrum 10.1351/goldbook.14059 14059 current 1 Plot of the photonic yield of a given photoprocess, measured at the same photon flux of incident (prior to absorption) light, as a function of a measure of the energy of the photons, i.e., for monochromatic irradiation. In practice, the photonic yield spectrum is obtained by normalising the rate of the given process to a certain number of incident photons provided that the photoresponse is linear on the incident photon fluence. Should the fluence dependence of the photoresponse be nonlinear (as is often the case in catalysed photoresponses), a plot of the photoresponse vs. fluence should be made at several wavelengths and a standard response should be chosen (e.g., two-lg reduction). A plot of the inverse of the "standard response" level as a function of wavelength is then the action spectrum of the photoresponse. Note that in photocatalysis the term yield is reserved for monochromatic irradiation, whereas the term efficiency is used for irradiation within a wavelength range. This is different from the use of efficiency as defined by IUPAC in photochemistry. photonic yield https://goldbook.iupac.org//terms/view/14058 PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 975 (https://doi.org/10.1351/PAC-REC-09-09-36) https://goldbook.iupac.org/terms/view/14059/html https://goldbook.iupac.org/terms/view/14059/json https://goldbook.iupac.org/terms/view/14059/plain Citation: 'photonic yield spectrum' 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.14059 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-06-21T19:40:35+00:00