Synthesis, Crystal Structures, and Photoluminescent Properties of Two Supramolecular Architectures Based on Difunctional Ligands Containing Imidazolyl and Carboxyl Groups

Two new supramolecular architectures, namely, [Cd(L1)2(H2O)]n (1) and [Ni(L2)2(H2O)]n (2), were synthesized by the reaction of corresponding metal salts of CdCl2·2.5H2O and NiCl2·6H2O with 2-(1H-imidazol-4-yl)benzoic acid (HL1) and 3-(1H-imidazol-4-yl)benzoic acid (HL2) respectively, and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and powder X-ray diffraction (PXRD). Both HL1 and HL2 ligands are deprotonated to be L1- and L2- anions that coordinate with Cd(II) and Ni(II) atoms to form two-dimensional (2D) layer structure. Topologically, complex 1 is a 2D network with (4, 4) sql topology, while 2 is a typical 63-hcb topology net. Complex 1 exhibits intense light blue emission in the solid state at room temperature.