Poly[[(μ(3)-5-amino-isophthalato-κO:O:N)(1H-imidazole-κN)zinc] 0.25-hydrate]

In the title coordination polymer, {[Zn(C(8)H(5)NO(4))(C(3)H(4)N(2))]·0.25H(2)O}(n), the Zn(2+) cation has an N(2)O(2) donor set involving two carboxyl-ate O atoms from two 5-amino-isophthalate anions, one N atom from a 5-amino-isophthalate anion, and one imidazole N atom displaying a slightly distorted tetra-hedral geometry with two additional O-atom neighbours, with Zn-to-ligand distances of 2.711 (2) and 2.717 (2) Å, respectively. Each 5-amino-isophthalate anion acts as a μ(3)-bridge linking symmetry-related Zn(II) ions into a layered polymeric structure parallel to (100). The asymmetric unit also comprises a disordered crystal water molecule located on an inversion centre with 0.25 occupancy. In the crystal, N-H⋯O hydrogen bonds form a three-dimensional network.