https://doi.org/10.1351/goldbook.R05063
Transfer of
excitation energy
by radiative deactivation
of a donor molecular entity and reabsorption of the emitted radiation by an acceptor molecular entity.Notes:
- Radiative transfer results in a decrease of the donor fluorescenceintensity in the region ofspectral overlap. Such a distortion of thefluorescencespectrum is called inner-filtereffect.
- Radiative energy transfer depends on the shape and size of the vessel utilized and on the configuration of the latter with respect to excitation and observation.
- The fraction
of photons emitted by D and absorbed by A is given by where is the molar concentration of acceptor, is thefluorescencequantum yieldin the absence of acceptor, is the thickness of the sample, and are thespectral distributionof thespectral radiant intensityof the donorfluorescenceand themolar decadic absorption coefficientof the acceptor, respectively, with thenormalizationcondition .
For relatively lowabsorbance, can be approximated by where the integral represents the overlap between the donorfluorescencespectrum and the acceptorabsorption spectrum.