a Escuela de Qu?́mica, Facultad de Ciencias, Universidad Central de Venezuela, Caracas, Venezuela
b Centro de F?́sica, Instituto Venezolano de Investigaciones Cient?́ficas, Apartado 21827,Caracas 1020A, Venezuela
Abstract:
Fluorescence spectral changes of Rhodamine 6G in ethanol and glycerol solutions and deposited as a film on a silica surface have been studied using a wide range of pumping field fluence at 532 nm at room temperature. Blue shift of the fluorescence spectra and fluorescence quenching of the dye molecule in solution are observed at high excitation fluence values. Such effects are not reported for the film sample. The effects are interpreted as the result of population redistribution in the solute-solvent molecular system induced by the high fluence field and the fluence dependence of the radiationless decay mechanism.