Poly[aqua[μ4‐3,3′‐(diazenediyl)dibenzoato]zinc]

The solvothermal reaction of Zn(OAc)₂·2H₂O with 3,3′‐(diazenediyl)dibenzoic acid (H₂ADB) in H₂O at 393 K afforded the title complex, [Zn(C₁₄H₈N₂O₄)(H₂O)]_n. The asymmetric unit contains half a Zn^II cation, half an ADB ligand and half a water molecule. Each Zn^II centre lies on a crystallographic twofold rotation axis and is five‐coordinated by four O atoms of bridging carboxylate groups from four ADB ligands and one O atom from a water molecule, forming a distorted trigonal–bipyramidal coordination geometry. The [Zn(H₂O)] subunits are bridged by carboxylate groups to give one‐dimensional [Zn(μ‐COO)₄(H₂O)]_n chains. The chains are linked by ADB ligands into two‐dimensional sheets, and these sheets are further connected to neighbouring sheets via hydrogen bonds (OW—HW...O), forming a three‐dimensional hydrogen‐bond‐stabilized structure with an unprecedented 3⁷4¹⁷5²6² topology.