catena-Poly[ammonium [aqua­bis­(μ-2,3,5,6-tetra­oxo-4-nitro­pyridin-4-ido)argentate(I)]]

In the title compound, {(NH(4))[Ag(C(5)HN(2)O(6))(2)(H(2)O)]}(n), the Ag(I) cation is seven-coordinated and is surrounded by four oxo O atoms of the 2,3,5,6-tetra­oxo-4-nitro­pyridin-4-ide species [Ag—O = 2.3848 (19), 2.4931 (18), 2.5361 (18) and 2.573 (2) Å], two nitro O atoms [Ag—O = 2.644 (2) and 2.661 (2) Å], and one water mol­ecule [Ag—O = 2.3133 (19) Å]. The pyridin-4-ide mono-anions act as polydentate bridging ligands and form a three-dimensional network that is stabilized through O—H⋯O and N—H⋯O hydrogen bonds involving the coordinating water mol­ecule and the imide function as donator groups. The ammonium cations are located in the cavities of the framework and are also involved in hydrogen bonding to O atoms of the ligand.