Detection, quantification, and magnetic field dependence of solid-state O-17 NMR of X-O-Y (X,Y = Si,Ti) linkages: Implications for characterizing amorphous titania-silica-based materials

O-17 solid-state NMR spectra from hybrid TiO2-SiO2-based materials can clea rly distinguish Si-O-Si, Si-O-Ti, and Ti-O-Ti linkages. Spectra are reporte d from these groups for applied magnetic fields from 5.6 to 14.1 T, which a llows their NMR parameters to be deduced. The quantitative accuracy of thes e spectra is investigated and the implications for detecting nanoscale phas e separation discussed. Changes in the local structure with functionalizati on of the silicon alkoxide (R'Si-lambda(OR)(4-x)) and modification of the t itanium precursor by acetylacetone are examined.