1 H spectra were referenced to adamantane at 1.81 ppm, C spectra to the tertiary carbon of adamantane at 38.5 ppm, F spectra to LiF at -203 ppm, Al spectra to AlF3 at -15 ppm, 93 Nb spectra to LiNbO3 at -1004 ppm , and 47/49 Ti spectra to the 49 Ti signal of SrTiO3 at -843 ppm.