P-31-]H-1 CROSS-POLARIZATION AND H-1 SPIN-DIFFUSION NMR IN THE LARGE-PORE GALLOPHOSPHATE MOLECULAR-SIEVE CLOVERITE

P-31 --> H-1 cross-polarization and H-1 spin diffusion assist in the a ssignment of the H-1 NMR peak at 6.4 ppm to structural P-OH groups in hydrated cloverite. The chemical shift confirms the high Bronsted acid ity of these groups, in agreement with the earlier ESCA and IR results .