A tetrahedrally coordinated Ag(I) and Ni(II) complex with a two-dimensional framework containing one-dimensional helical chains.

The title complex, poly[bis(mu(6)-pyridine-2,6-dicarboxylato N-oxide)nickel(II)disilver(I)], [Ag(2)Ni(C(7)H(3)NO(5))(2)](n) or [Ag(2)Ni(pydco)(2)](n) (H(2)pydco = pyridine-2,6-dicarboxylic acid N-oxide), has a two-dimensional sheet structure. The two carboxylate groups adopt two coordination modes. The Ni(II) ion displays a distorted octahedral geometry, bonded to two carboxylate O atoms of two different pydco ligands and four O donors from another two ligands, i.e. two carboxylate O atoms and two N-oxide O atoms. The Ag(I) ion adopts a tetrahedral coordination, linked by three O atoms of three different carboxylate groups and an N-oxide O atom.