Crystal structure of poly[di­aqua­bis­(μ(5)-benzene-1,3-di­carboxyl­ato)(N,N-di­methyl­formamide)­cadmium(II)disodium(I)]

The title compound, [CdNa(2)(C(8)H(4)O(4))(2)(C(3)H(7)NO)(H(2)O)(2)](n) or [CdNa(2)(1,3-bdc)(2)(DMF)(H(2)O)(2)](n), is a new Cd(II)–Na(I) heterobimetallic coordination polymer. The asymmetric unit consists of one Cd(II) atom, two Na(I) atoms, two 1,3-bdc ligands, two coordinated water mol­ecules and one coordinated DMF mol­ecule. The Cd(II) atom exhibits a seven-coordinate geometry, while the Na(I) atoms can be considered to be penta­coordinate. The metal ions and their symmetry-related equivalents are connected via chelating–bridging carboxyl­ate groups of the 1,3-bdc ligands to generate a three-dimensional framework. In the crystal, there are classical O—H⋯O hydrogen bonds involving the coordinated water mol­ecules and the 1,3-bdc carboxyl­ate groups and π–π stacking between the benzene rings of the 1,3-bdc ligands present within the frameworks.