A novel two-dimensional coordination polymer: poly[di­aqua­tetra-[mu]₂-chlorido-[[mu]₂-2,2'-(piperazine-1,4-di­ium-1,4-di­yl)di­acetate]­di­cadmium(II)]

In the crystal structure of the title two-dimensional metal-organic polymeric complex, [Cd₂Cl₄(C₈H₁₄N₂O₄)(H₂O)₂]_n, the asymmetric unit contains a crystallographically independent Cd^II cation, two chloride ligands, an aqua ligand and half a 2,2'-(piperazine-1,4-diium-1,4-di­yl)di­acetate (H₂PDA) ligand, the piperazine ring centroid of which is located on a crystallographic inversion centre. Each Cd^II centre is six-coordinated in an octa­hedral environment by an O atom from an H₂PDA ligand and an O atom from an aqua ligand in a trans disposition, and by four chloride ligands arranged in the plane perpendicular to the O-Cd-O axis. The complex forms a two-dimensional layer polymer containing [CdCl₂]_n chains, which are inter­connected into an extensive three-dimensional hydrogen-bonded network by C-H...O, C-H...Cl and O-H...O hydrogen bonds.