Synthesis and characterization of a new series of nickel dithiolate compounds containing both acridinium cations and halogen anions

A new class of [Ni(dmit)2]− compounds, [AcrH][Ni(dmit)2][MeOH] (1), [AcrH]2[Ni(dmit)2][Cl] (2), [AcrH]2[Ni(dmit)2][Br] (3) (where AcrH represents protonated acridinium) have been synthesized. The as synthesized compounds were characterized by ESI-MS, IR, UV–Vis and X-ray crystallography. We show that small changes in the chemical composition of these salts lead to significant difference in their crystal structure and physical properties. As compared to compounds 2 and 3, compound 1 exhibits better conductivity and stronger anti-ferromagnetic interaction owning to shorter S⋯S distances. Compound 1 can self-assemble into high crystalline rod-shape crystals due to the abundant inter-molecular interactions. Compounds 2 and 3 represent the first examples where the halogen anions are incorporated into the separated sheets of Ni(dmit)2 units.