Poly[bis(4-chloropyridinium) tetra-μ2-chlorido-tetrachloridotrimercurate(II)]

The structure of the title compound, {(C5H5ClN)2[Hg3Cl8]}n, consists of 4-chloropyridinium cations and one-dimensional [Hg3Cl8]2−anion chains. There are two coordination environments for HgIIin the inorganic chain. The first is a distorted tetrahedral geometry made up of an HgCl2unit with two Cl−anion bridges, while the second is an octahedral coordination geometry consisting of an HgCl2unit and four chloride-anion bridges. This gives rise to a novel three-layer centrosymmetric polymer. Finally, the three-dimensional network comes about through the many C—H...Cl and N—H...Cl hydrogen bonds that link the organic and inorganic layers.