4,4′-(Ethene-1,2-diyl)dipyridinium 4-[2-(pyridin-4-yl)ethenyl]pyridinium octacyanidomolybdate(V) tetrahydrate

The crystal structure of the title compound, (C12H12N2)(C12H11N2)[Mo(CN)8]·4H2O, consists of 4,4′-(ethene-1,2-diyl)dipyridinium and 4-[2-(pyridin-4-yl)ethenyl]pyridinium cations disordered over the same site, an [Mo(CN)8]3− anion and four water molecules of crystallization. The eight-coordinate [Mo(CN)8]3− unit exhibits a slightly distorted square-antiprismatic geometry. In the structure, the cations (crystallographic symmetry, 2) and anions (crystallographic symmetry, 222) are arranged alternately by N—H⋯O and O—H⋯N hydrogen bonds, forming layers parallel to the bc plane. These layers are further linked through O—H⋯N hydrogen bonds, generating a three-dimensional supramolecular network.