of reference GaIV, GaV, and GaVI compounds by MAS and QPASS, extension of gallium/aluminum NMR parameter correlation

We report new measurements of NMR parameters for 71 Ga in gallium bearing oxide reference compounds, ranging from perfectly ordered systems to disordered crystalline structures and their aluminate counterparts. Static, MAS, and QPASS spectra are obtained at magnetic fields ranging from 7.0 to 18.8 T. With these results we enhance the previously established correlation between isotropic chemical shifts of 71 Ga and 27 Al and propose a correlation between gallium and aluminum electric field gradients (EFG). This correlation shows that the EFG at 71 Ga sites are generally three times greater than those at equivalent 27 Al sites.