Abstract
The water-coordinated metal centre in the title salt, [Zn(C(12)H(8)N(2))(2)(H(2)O)(2)]C(7)H(4)O(6)S·4H(2)O, is chelated by the two bidentate N-heterocycles, leading to an overall distorted octa-hedral environment. The cation, dianion and solvent water mol-ecules inter-act by O-H⋯O hydrogen bonds to form a layer motif. The SO(3) group is disordered over two positions with respect to the O atoms in a 0.76 (1):0.24 (1) ratio. One of the solvent water molecules is also disordered over two positions in a 0.56 (4):0.44 (4) ratio.