Poly[[hexa­aqua­bis[μ₄-2-hydr­oxy-5-(4-sulfonatophenyl­diazen­yl)­benzoato]­dibarium(II)] 4,4′-bipyridine solvate]

The title compound, {[Ba₂(C₁₃H₈N₂O₆S)₂(H₂O)₆]·C₁₀H₈N₂}_n, possesses a novel two-dimensional porous coordination network, in which each Ba^II ion is nine-coordinated by three carboxyl­ate O atoms, two sulfonate O atoms and four water mol­ecules in an irregular coordination environment. Hydrogen-bond inter­actions between coordinated water mol­ecules and sulfonate/hydroxyl groups hold the network layers together and produce a three-dimensional supra­molecular architecture.