Radiative energy transfer II. The effect of radiative transfer on the monomer to excimer ratio in a binary system

The equations derived in part I of this series to obtain the correction for radiative energy transfer when the observation of the fluorescence emission is made from the same face of the cell where excitation takes place are applied to the case where pyrene (Py) is the energy donor and 9,10-diphenylanthracene (DPA) is the energy acceptor. It is shown that the magnitude of the correction is quite large and that to neglect it could lead to important errors, when analysing the results regarding the possibility of a nonradiative energy transfer from Py excimers. Different methods of correcting the overall energy transfer efficiencies already published are critically reviewed.