https://doi.org/10.1351/goldbook.R05046

power emitted, transferred or received as radiation. SI unit is J s-1 = W.**Notes: **

*Source: *

PAC, 2007,*79*, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 410 (https://doi.org/10.1351/pac200779030293)

- Mathematical definition: \(P = \text{d}Q/\text{d}t\). If the @R05039@ \(Q\) is constant over the time interval, \(P = Q/t\).
- In @R05115@, flux (\(\varPhi\)) is used with the same units as \(P\). The symbol \(\varPhi\) is reserved for @Q04991@ in @P04588@. Therefore, the use of flux (\(\varPhi\)) is not recommended.

PAC, 2007,