Diguanidinium bis­(μ-2-hydroxy­propane-1,2,3-tricarboxyl­ato)bis­[diaqua­zincate(II)] dihydrate

The asymmetric unit of the title compound, (CH(6)N(3))(2)[Zn(2)(C(6)H(5)O(7))(2)(H(2)O)(2)]·2H(2)O, contains one-half of a centrosymmetric dizinc(II) complex anion, one guanidinium cation and one water mol­ecule. Each Zn(II) ion is hexa­coordinated by two citrate anions, one in a bidentate fashion and the second monodentate, and two water mol­ecules in a distorted octa­hedral geometry. Intra­molecular O—H⋯O hydrogen bonds add further stability to the mol­ecular structure. In the crystal structure, mol­ecules are linked into a three-dimensional framework by inter­molecular N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds.