Hydrogen-bonded layers directed by the [3-O3S-C6H4-PO3H]2- dianio: catena-poly[[silver(I)-μ-4,4′-bipyridine-Κ²N:N′] 3-[hydroxy(oxido)phosphinoyl]benzenesulfonate trihydrate] and catena-poly[[[tetraaquacobalt(II)]-μ4,4′-bipyridine-Κ²N:N′] 3-[hydroxy-(oxido)phosphinoyl]benzenesulfonate].

The article describes how a previously unreported dianion can affect the crystallization of polymeric metal complex cations. The structures of both title compounds are described in detail. It examines the two-coordinate Ag structure features of the title compounds. Also illustrated are the two-dimensional supramolecular layered architectures of the title compounds.