Di-μ-chlorido-bis-{[2-(benzyl-imino-meth-yl)pyridine-κN,N']chloridomercury(II)} dichloridomercury(II).

The Hg(II) ion in the title centrosymmetric dinuclear complex, [Hg(2)Cl(4)(C(13)H(12)N(2))(2)]·[HgCl(2)], adopts a distorted square-pyramidal geometry, being coordinated by the bis-chelating N-heterocyclic ligand, two bridging Cl atoms and one terminal Cl atom. One of the bridging Hg-Cl bonds [2.8428 (11) Å] is significantly longer than the other [2.5327 (10) Å]. In the crystal, there are weak π-π inter-actions [centroid-centroid distance = 3.630 (3) Å] between the aromatic rings of the discrete units. The HgCl(2) adduct molecule is located on an inversion centre and has an Hg-Cl bond length of 2.2875 (11) Å.