Structure of 2,2′-(5-tert-butyl-1,3-phenyl­ene)bis­­(1-pentyl-1H-benzimidazol-3-ium) tetra­chlorido­mercurate(II)

In the title salt, (C34H44N4)[HgCl4], the [C34H44N4]2+ cations and [HgCl4]2− anions are linked by N—H⋯Cl hydrogen bonds. One of the two n-pentyl side chains was refined as disordered over two sets of sites, with occupancies of 0.733 (18) and 0.267 (18). The geometry around the HgII atom in the [HgCl4]2− anion is distorted tetra­hedral, with bond angles ranging from 98.16 (3) to 120.68 (3)°. In the [HgCl4]2− anion, there are two short Hg—Cl bonds [2.4120 (9) and 2.4171 (11) Å], one inter­mediate Hg—Cl bond [2.4716 (12) Å] and one long Hg—Cl bond [2.6579 (13) Å] for the Cl atom involved in a trifurcated hydrogen bond as an acceptor, including two N—H⋯Cl⋯H—N interactions as well as one C—H⋯Cl inter­action. There are several C—H⋯Cl inter­actions, with C⋯Cl distances ranging from 3.492 (3) to 3.796 (3) Å. These link the cations and anions into a zigzag chain along the c-axis direction. In addition, there are Cl⋯Cl halogen bonds, as well as π–π inter­actions, with centroid-to-centroid distances of 3.4765 (18) Å, which link one of the two benzimidazole moieties into dimeric units.