Solvent water tapes in two hydrates of mu-oxo-bis[bis(2,2'-bipyridine-kappa2N,N')(sulfato-kappaO)iron(III)].

The title compound, [Fe2O(SO4)2(C10H8N2)4], crystallizes as two different hydrates, viz. 11H2O, (I), and 15H2O, (II). The complex is binuclear, in which the two FeIII atoms are coordinated in an octahedral geometry to four N atoms from the two bipyridine ligands, to one O atom from the sulfate ion and to an oxide ion on a twofold axis, which acts as a bridge between the symmetry-related units.