Inorganic–organic hybrid materials produced by the sol–gel method from Si (OR) 4 and R′
x− ySi (OR) y (R, R′—CnHm groups) compounds are very interesting materials for new
optical techniques. Recognition of the structure of these materials is very important for
controlling their production process as well as their properties. Five different hybrid gels
were obtained using tetraethoxysilane (TEOS) with addition of the following modifiers:
methyltrimethoxysilane (MTMS)(CH3) Si (CH3O) 3, vinyltriethoxysilane (VTES)(CHCH2) Si …