The primary results included a striking similarity in the behavior of an F' defect center signal in the in situ EPR and a band at 1599 cm-1 in the UV-Raman for the 12 and 60% TiO2/SiO2 catalysts, suggesting a possible induced Raman signal that could be used as an indirect method for tracking photocatalytic behavior. The EPR studies also showed that the F' defect center thermally most stable on the 12% TiO2/SiO2 catalyst. It is known from the structural characterization studies that the 12% TiO2/SiO2 catalysts consists entirely of polymeric surface chain nanostructures. Thus, the polymeric surface titania chain is preferential for the formation of F' center defects and, thus, preferential for photocatalytic activity. The DRIFT study revealed that the adsorption of propylene was preferential to acetone intermediates as evidenced by vibrations at 1688 and 1421 cm-1 under reaction gas flow and UV irradiation. Furthermore, the studies showed that catalysts containing crystalline nanodomains more readily formed the acetone surface species. Catalysts promoted with WOx species were also examined and showed no difference in the adsorption spectra.