Abstract: Three complexes with 3,5-dinitrobenzoic acid (DNBC) and imidazole (Im) ligands Zn(DNBC)2(Im)2 (1), Cu(DNBC)2(Im)(H2O) (2), Co1.5(DNBC)4(Im)(CH3OH) (3) were synthesized in water-methanol mixture solution and characterized by elemental analysis, IR spectra. Their crystal structures were determined by single crystal X-ray diffraction. The c complex 1 possesses tridimensional netlike supramolecular structure which is formed by intermolecular hydrogen bonding and Van der Waals force, where each Zn(II) is in 2O+2N coordination modes, each four-coordinated Zn(II) ions form a distorted tetrahedral geometry. The complex 2 has a 1D zigzag chain networks, where each Cu(II) is in 4O+N coordination modes, and each five-coordinated Cu(II) ions form a distorted square-pyramidal geometry. The complex 3 crystallizes in the monoclinic system with space group P2(1)/n, a = 1.20876(7)nm, b = 2.63287(16)nm, c = 1.36466(9)nm, V = 4.3045(5)nm3, Z = 4, F(000) = 2166, the adjacent Co…Co distance of 0.3587nm. Complex 3 possesses 1D zigzag chain composed by Co(II) and by μ-OH2, while triple-clear of octahedral Co(II) bridged by μ-OH2 further connected through the hydrogen bonding to adjacent triple-clear Co(II). Thus, the aggregation of the coordination units through O–H…O hydrogen bonds, results in the formation of channels, which are occupied by imidazole molecules and methanol molecules. Magnetic measurements of complex 3 indicate antiferromagnetic interactions between adjacent Co(II) ions within the trimer.

Key words: 3,5-Dinitrobenzoic acid; , Imidazole; , Complex; , Crystal structure