Poly[[penta­aqua­sulfato-μ₄-(R,R)-tartrato-dicadmium(II)] trihydrate]

The asymmetric unit in the title compound, {[Cd₂(C₄H₄O₆)(SO₄)(H₂O)₅]·3H₂O}_n, is composed of two cadmium cations, one (R,R)-tartrate and one sulfate anion, five aqua ligands and three solvent water mol­ecules. One of the cadmium ions is coordinated in an octa­hedral environment, whereas the second is surrounded by seven O atoms in a penta­gonal–bipyramidal geometry. Both types of coordination polyhedra form two sets of perpendicular non-inter­secting polymeric chains. CdO₆ octa­hedra share two corners, while CdO₇ units are joined by a bridging carboxyl­ate group. An extensive hydrogen-bond pattern involving all of the OH groups contributes to the stabilization of the structure.