In situ preparation, structure, fluorescence and TDDFT calculations of [(CdCl3)2(μ2-HCl)]2[CdCl4(HCl)][N,N′-dimethyl-4,4′-bipyridinium]3

A novel cadmium-4,4'-bipyridinium compound, [(CdCl3)(2)(mu 2HCl)](2)[CdCl4(HCl)][N,N'-dimethyl-4,4'-bipyridinium](3) (1) in which the N,N'-dimethyl-4,4'-bipyridinium moiety is obtained in situ, has been synthesized via a solvothermal reaction and characterized by X-ray diffraction analyses. Compound (1) crystallizes in the P31c space group of rhombohedral system. The [(CdCl3)(2)(mu(2)-HCl)](2-) anion, [CdCl4(HCl)](2-) anion and [N,N'-dimethyl-4,4'-bipyridinium](2+) cation are interlinked through hydrogen bonding interactions to yield a three-dimensional supramolecular network Fluorescence investigation reveals that compound (1) displays an intensive emission band in the green region. In combination with the theoretical studies, it may be concluded that the emission band originates mainly from the ligand-to-ligand charge-transfer transition, accompanied by a minor metal-to-ligand charge-transfer (MLCT) transition.