Coordination preference of 1,2-bis((1H-imidazole-1-yl)methyl)benzene and different carboxylate ligands with transition metal ions directed by weak interactions

Abstract

Three novel metal-organic complexes, formulated as [Cu2(2-HBA)2(bimb)4] (1), {[Cd(CEDA)(bimb)]·H2O}n (2), and {[Ag2(bimb)2]·(1,4-CDA)·13H2O} (3) (bimb = 1,2-bis((1H-imidazole-1-yl)methyl)benzene; 2-HBA = 2-hydroxybenzoic acid; CEDA = cyclohex-4-ene-1,2-dicarboxylic acid; 1,4-CDA = cyclohexane-1,4-dicarboxylic acid), were synthesized by self-assembly of mixed ligands with Cu(II), Cd(II), and Ag(I) under hydrothermal conditions and characterized by means of single-crystal X-ray diffraction, X-ray powder diffraction, infrared spectra, thermogravimetric analysis, fluorescence spectra and UV–vis absorption spectra. 1 is shown as a 0D structure, which is formed by Cu2+, 2-HBA ligands and bimb ligands. 2 displays a 1D ladder structure, which is built by Cd2+, CEDA ligands and bimb ligands, and it is assembled into 2D structure by hydrogen bonding. 3 possesses a 0D [Ag(bimb)]2 dimer which is assembled into 3D structure by the AgO weak interaction and hydrogen bonding. Interestingly, a rare 13-core water cluster participates in forming the network of 3. The UV–vis spectrum and luminescence properties were also studied and discussed.