catena-Poly[[tetra-aqua-zinc(II)]-μ-2,2'-dihydr-oxy-5,5'-diazenediyldibenzoato].

In the title compound, [Zn(C14H8N2O6)(H2O)4]n, the 2,2′-dihydr­oxy-5,5′-diazenediyldibenzoate ligand acts as a carboxyl­ate bridge, leading to the formation of a polymeric chain running along the [1\overline{1}0] direction. The ZnII atom is hexa-coordinated in a distorted octa­hedral geometry by six O atoms [Zn—O = 2.055 (4)–2.132 (3) A] from two carboxylate ligands and four water mol­ecules. The crystal packing is stabilized by inter­molecular O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds, and two π–π inter­actions. The centroid–centroid distances are 3.803 (16) and 3.804 (17) A.