Optical investigation on dye-doped sol-gel glasses

We have investigated the optical properties of the 3,3'-diethyloxadicarbocyanine iodide (DODCI) dye incorporated in a number of sol-gel glasses in order to study the interaction between the trapped molecule and the host matrix. The differences found in both the absorption and the photoemission spectra demonstrate that the excitation processes of the dye molecule are influenced by the chemical reactivity and the degree of porosity of the surrounding network. We have found that while the molecular photoisomerization is quenched in all the matrices, for the modifications of the electronic excited states the high rigidity of the purely inorganic silica matrix is required. Conversely, the possibility of chemical attacks to the molecular conjugate chain seems to increase in the hybrid organic/inorganic ormosil matrices.