Poly[[diaqua­bis­(μ(3)-isonicotinato-κ(3) N:O:O′)bis­(μ(2)-isonicotinato-κ(2) N:O)gadolinium(III)disiliver(I)] nitrate monohydrate]

In the title compound, {[Ag(2)Gd(C(6)H(4)NO(2))(4)(H(2)O)(2)]NO(3)·H(2)O}(n), the Gd(III) ion is coordinated by eight O atoms from six isonicotinate ligands and two water mol­ecules in a distorted square anti­prismatic geometry. Two Ag(I) ions are each bonded to two N atoms from two isonicotinate ligands in a linear or bow-like fashion [N—Ag—N angles = 178.6 (2) and 147.1 (2)°]. These metal ions are connected by the isonicotin­ate ligands into a layer parallel to (010). O—H⋯O hydrogen bonds donated by the coordinated and uncoordinated water mol­ecules and intra­layer π–π stacking inter­actions between the pyridine rings [centroid–centroid distances = 3.551 (4) and 3.555 (4) Å] are observed. The layers inter­act with each other by inter­layer Ag⋯O(aqua) contacts [2.731 (4) Å] and π–π stacking inter­actions between the pyridine rings [centroid–centroid distances = 3.466 (3) and 3.516 (3) Å], resulting in the formation of a three-dimensional supra­molecular structure.