Crystal structure of a two-dimensional grid-type iron(II) coordination polymer: poly[[di­aqua­tetra-μ-cyanido-diargentate(I)iron(II)] trans-1,2-bis(pyridin-2-yl)ethyl­ene disolvate]

In the title compound, {[Ag(2)Fe(CN)(4)(H(2)O)(2)]·2C(12)H(10)N(2)}(n), the asymmetric unit contains one Fe(II) cation, two water mol­ecules, two di­cyanido­argentate(I) anions and two uncoordinating 1,2-bis­(pyridin-2-yl)ethyl­ene (2,2′-bpe) mol­ecules. Each Fe(II) atom is six-coordinated in a nearly regular octa­hedral geometry by four N atoms from di­cyanido­argentate(I) bridges and two coordinating water mol­ecules. The Fe(II) atoms are bridged by di­cyanido­argentate(I) units to give a two-dimensional layer with square-grid spaces. The inter­grid spaces with inter­layer distance of 6.550 (2) Å are occupied by 2,2′-bpe guest mol­ecules which form O—H⋯N hydrogen bonds to the host layers. This leads to an extended three-dimensional supra­molecular architecture. The structure of the title compound is compared with some related compounds containing di­cyanido­argentate(I) ligands and N-donor organic co-ligands.