catena-Poly[[[triaquacadmium(II)]-μ-2,2′-[oxalylbis(azanediyl)]diacetato-κ2O,O′] dihydrate]

The structure of the polymeric title complex, {[Cd(C6H6N2O6)(H2O)(3)]center dot 2H(2)O}(n), consists of chains running parallel to [(1) over bar 01] in which the oxamidato ligand, deprotonated only at the carboxylate groups, acts as a bridging bis-monodentate ligand. The Cd atom and the O atom of a coordinated water molecule are located on a twofold axis. The coordination geometry around the Cd atom is distorted trigonal-pyramidal. In the crystal structure, neighbouring chains are linked into a three-dimensional network by interchain O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonds.