Crystal structures, luminescence, and DFT study of mixed-ligand Zn(II) and Cd(II) complexes with phenyl-containing benzimidazole derivatives with linker C N or N N group

Abstract The peculiarities of photoluminescence of zinc(II) and cadmium(II) compounds with benzimidazole derivatives L1 (1-methylbenzimidazo-2-yl-methyleneaniline) and L2 (1-ethyl-2-(4-methoxyphenyl)azobenzimidazole) containing electron-donating ligands Cl–, NO3–, or [B10H10]2– were studied. It was found that most compounds with L1 are green luminophores, while compounds with L2 are red luminophores. The intensity of the luminescence and the position of the emission band depending on the composition and structure of the complexes were analyzed. The use of the single-crystal X-ray diffraction data and the density functional theory (DFT) calculations made it possible to determine the general relationships between the structural and spectroscopic characteristics of the compounds.