absorbed (spectral) photon flux density

Number of photons of a particular @W06659@ per time interval (@S05821@, number basis, \(q_{\text{p},\lambda }\), or @S05821@, amount basis, \(q_{n,\text{p},\lambda }\)) absorbed by a system per volume, \(V\). On number basis, SI unit is \(\text{s}^{-1}\ \text{m}^{-4}\), and the common unit is \(\text{s}^{-1}\ \text{cm}^{-3}\ \text{nm}^{-1}\). On amount basis, SI unit is \(\text{mol s}^{-1}\ \text{m}^{-4}\), and a common unit is \(\text{einstein}\ \text{s}^{-1}\ \text{cm}^{-3}\ \text{nm}^{-1}\).
  1. Mathematical expression: \(\frac{q_{p,\lambda }^{0}[1 - 10^{-A(\lambda )} ]}{V}\) on number basis, \(\frac{q_{n,p,\lambda }^{0}[ 1 - 10^{-A(\lambda )} ]}{V}\) on amount basis, where \(A(λ)\) is the @A00028@ at @W06659@ \(λ\) and superscript \(0\) (zero) indicates incident photons.
  2. Absorbed spectral photon flux density (number basis or amount basis) should be used in the denominator when calculating a differential @Q04991@ and using in the numerator the rate of change of the number concentration, \(\frac{dC}{dt}\) or the rate of change of the @A00295@, \(\frac{dc}{dt}\), respectively.
PAC, 2007, 79, 293. (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 297 [Terms] [Paper]