relative photonic efficiency

symbol: $\xi_{\rm{rel}}$
https://doi.org/10.1351/goldbook.14084
Ratio of the photonic efficiency (\(\xi\)) of a chemical process to the corresponding photonic efficiency of a standard process under otherwise identical conditions in the same reactor configuration and operation.
Notes:
  1. For measurements carried out at constant photon flux, \(\xi_{\rm{rel}}\) can be estimated as the ratio of the corresponding reaction initial rates (for \(t \to 0\)), determined under identical conditions.
  2. Protocols for the determination of \(\xi_{\rm{rel}}\) have been reported.
  3. See the restrictions about the determination of quantum yields in photocatalysis mentioned in the Introduction of the source IUPAC Recommendation.
Source:
PAC, 2011, 83, 931. (Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)) on page 986 [Terms] [Paper]