Bis[diaquabis(2,2-bipyridine N,N'-dioxide-kappa2O,O')cobalt(II)] xi-octamolybdate dihydrate.

The title organic-inorganic hybrid compound, [Co(C(10)H(8)N(2)O(2))(2)(H(2)O)(2)](2)[Mo(8)O(26)].2H(2)O, consists of [Co(bpdo)(2)(H(2)O)(2)](2+) (bpdo is 2,2-bipyridine N,N'-dioxide) and xi-[Mo(8)O(26)](4-) groups in a 2:1 ratio, plus two water solvent molecules. The independent Co atom in the cation is coordinated by four O atoms from two bpdo ligands and two water molecules, in a distorted octahedral geometry. The counter-anions, built up around a symmetry center, are linked by solvent water molecules through O-H...O hydrogen bonds to generate two-dimensional layers, which are in turn linked by coordinated water molecules from the cationic units through further O-H...O hydrogen bonds, forming a three-dimensional supramolecular structure.