PHOTOCHROMISM AS A PROBE OF GELLATION IN ALUMINOSILICATE GELS DOPED WITH SPIROOXAZINE

Aluminosilicate gels containing photochromic ,3-trimethylindolo-2,3'-n aphth[1,2-b]-1,4-oxazine) were prepared by the sol-gel route. The spir ooxazine compound has been used as a photochromic probe for studying t he sol to gel transitions of aluminosilicate host gels. Absorption and luminescence spectroscopy were used to elucidate physicochemical chan ges to the gel network. The photochromic probe compound was found to b e very sensitive to local changes that occur during the gel formation process.