The photochemical method and technique by which a variety of optical structures such as channel waveguides, gratings and GRIN lenses, can be patterned in a porous glass host, have been extended to the stable formation of a number of semiconducting compounds of the III-V, II-VI, and IV-VI families, within the porous glass. The specific compounds prepared are CdS, CdSe, PbS ,PbSe, MoS2, and GaAs. In certain of these cases the reaction is optically initiated thus prescribed geometric structures are obtained. The unique microstructure provided by the porous glass, average pore diameter of 4nm with 30 percent pore volume, leads to small microcrystal size in the quantum confined regime. Optical absorption and photoluminescence data are shown to support this.