Expressions for the quantum yield of fluorescence of aromatic hydrocarbons in benzene and alkylbenzenes have been derived assuming zero internal quenching. These expressions indicate that the molecular quantum yield of fluorescence increases with (a) the lifetime of the first excited singlet state of the solvent (b) the transition probabilities from thenlevels of the solute that correspond to the levels involved in the excitation of the solvent and (c) the increase in the degree of degeneracy in the solute levels corresponding to those involved in the excitation of the solvent.nMinimum values of the molecular quantum yield of fluorescence of a group of aromatic hydrocarbons have been computed at different concentrations of the solutes.
展开▼
