Poly[[diaquabis(μ3-3-carboxylato-4-hydroxybenzenesulfonato)tri-μ2-pyrazine-tetrasilver(I)] dihydrate]

The title coordination polymer, {[Ag4(C7H4O6S)2(C4H4N2)3(H2O)2]·2H2O}n, contains two independent AgI ions. One AgI ion is coordinated by one O atom from a 3-carboxylato-4-hydroxybenzenesulfonate (L) ligand, two N atoms from two pyrazine ligands and a water molecule. The other AgI ion is coordinated by two O atoms from two L ligands and one N atom from a pyrazine ligand. One of the pyrazine ligands lies on an inversion center. The L and pyrazine ligands link the AgI ions into polymeric layers parallel to the ac plane. The layers are connected by intermolecular O—H...O hydrogen bonds. An intramolecular O—H...O hydrogen bond is also present in the L ligand