Poly[[tetra-aqua-bis-(μ(3)-5-carboxybenzene-1,2,4-tri-carboxyl-ato)tricadmium] tetra-hydrate]

There are three independent Cd(II) ions in the title complex, {[Cd(3)(C(10)H(3)O(8))(2)(H(2)O)(4)]·4H(2)O}(n), one of which is coordinated by four O atoms from three 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by two water mol-ecules in a distorted octa-hedral geometry. The second Cd(II) ion is coordinated by five O atoms from four 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by one water mol-ecule also in a distorted octa-hedral geometry while the third Cd(II) ion is coordinated by five O atoms from three 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands and by one water mol-ecule in a highly distorted octa-hedral geometry. The 5-carboxybenzene-1,2,4-tri-carboxyl-ate ligands bridge the Cd(II) ions, resulting in the formation of a three-dimensional structure. Intra- and inter-molecular O-H⋯O hydrogen bonds are present throughout the three-dimensional structure.