Stabilization of the previously unknown tautomer HP(OH) 2 of hypophosphorous acid as ligand; preparation of [W 3 (Ni(HP(OH) 2 ))Q 4 (H 2 O) 9 ] 4+ (Q = S, Se) complexes

Bis(hydroxy)phosphine, the isomer of hypophosphorous acid which remained elusive for a long time, coordinates to the Ni site of heterometallic clusters with a W3NiQ4 core (Q = S, Se) to give [W3(Ni(HP(OH)2))Q4(H2O)9]4+ (Q = S, Se).