Molecular Aggregation and Deaggregation of Rhodamine 6G in the Formation of Hybrid Sol–Gel Films

Electronic and fluorescence spectroscopy was used to show that the aggregation of rhodamine 6G molecules in a film-forming sol and derived hybrid films is a function of the equilibrium dye concentration and the micelle-forming agent and, as a consequence, the concentration of the micelle-forming agent in the film-forming sol affects the optical characteristics of the hybrid sol–gel films. Dye monomers were found to predominate in the sol, while the formation of nonplanar luminescent H-dimers is possible during film formation as a consequence of geometrical limitations of the dye molecules solubilized within the micelles.