Poly[[diaqua­tris(μ(2)-4,4′-bi­pyridine)­bis[μ(2)-2-(carb­oxylato­methyl­sulfan­yl)nicotinato]dicobalt(II)] 1.3-hydrate]

The title complex, [Co(2)(C(8)H(5)NO(4)S)(2)(C(10)H(8)N(2))(3)(H(2)O)(2)]·1.3H(2)O, was synthesized under hydro­thermal conditions. The Co(II) ion is six-coordinated in a slightly distorted octa­hedral environment resulting from two carboxyl­ate O atoms of two 2-carb­oxy­methyl­sulfanyl nicotinate (2-CMSN(2−)) anions, one water mol­ecule and three N atoms of three 4,4′-bi­pyridine ligands, with one 4,4′-bi­pyridine ligand situated on a centre of inversion. Two neighboring Co(II) ions are linked by two anions, giving a dinuclear [Co(2)(2-CMSN)(2)] subunit with a Co⋯Co separation of 6.8600 (3) Å. The dinuclear subunits are joined by bridging 4,4′-bi­pyridine linkers, generating a three-dimensional network structure. Disordered water mol­ecules are situated in the free space of this network. O—H⋯O hydrogen bonding within and between the subunits enhances the stability of the structure.