Résumé
High resolution super(43)Ca solid-state NMR studies of hydroxyapatite (Ca sub(10)(PO sub(4)) sub(6)(OH) sub(2)) were performed at 14.1 T. The two crystallographically distinct calcium sites were unequivocally resolved by a triple-quantum magic angle spinning experiment, and the unambiguous assignment of the signals was possible using super(1)H- super(43)Ca rotational echo double resonance and super(1)H- super(43)Ca cross polarization magic angle spinning experiments.