31P → 1H cross-polarization and 1H spin diffusion NMR in the large-pore gallophosphate molecular sieve cloverite

31P → 1H cross-polarization and 1H spin diffusion assist in the assignment of the 1H NMR peak at 6.4 ppm to structural POH groups in hydrated cloverite. The chemical shift confirms the high Brønsted acidity of these groups, in agreement with the earlier ESCA and IR results.