Influence of the temperature of preparation process on refractive index ofsol-gel matrices

The preparation of sol-gel materials in the form of bulks and thin films at different temperatures is described. The procedure involves running the re action at 50 degreesC and 90 degreesC in an open vessel. Such an approach e nables acceleration of hydrolysis and condensation reactions. This procedur e yelds crack-free sol-gel glasses. The changes in refractive index of sol- gel materials were studied by using Pulfrich refractometer. The experimenta l data indicates significant differences in the optical properties of sol-g el glasses, depending on the temperature during the preparation The samples show normal dispersion, whereas a higher refractive index was stated for f ilms prepared at a higher temperature.