catena-Poly[[diiodidomercury(II)]- #956;2-2-aminopyrazine- #954;2N1:N4]

In the crystal of the title polymeric compound, [HgI2(C4H5N3)]n, the HgII cation is located on a twofold rotation axis and is coordinated by two I− anions and two 2-aminopyrazine ligands in a distorted HgI2N2 tetrahedral geometry. In the crystal, the 2-aminopyrazine ligand is equally disordered over two positions about an inversion center, and bridges the HgII cations with pyrazine N atoms to form a polymeric chain running along the c axis. In the polymeric chain, the amino groups link to the coordinated I− anions via intermolecular N—H...I hydrogen bonds.