Hydrothermal synthesis, crystal structure and thermal analysis of a dinuclear complex Cd₂(3,5-dinitrobenzoate)₄(pyridine) ₄

A dinuclear complex Cd₂(dnba)₄(pyridine)₄ (dnba = 3,5-dinitrobenzoate) has been synthesized by hydrothermal method and characterized by X-ray single-crystal diffraction, elemental analysis, FT-IR spectroscopy, DSC and TG-DTG techniques. The complex with empirical formula C₄₈H₃₂Cd₂N₁₂O₂₄. (M _r = 692.83) crystallizes in monoclinic, space group P2₁/n with a = 12.0344(14), b = 10.5752(13), c = 21.578(3) Å, β= 104.150(2)°, V = 2662.8(6) ų, Z = 2, D_c = 1.728 g/cm³, μ(MoKa) = 0.897 mm^-1, F(000) = 1384, S = 1.016 and (Δ/σ)_max = 0.001. R = 0.0638 and wR = 0.0737 for all data; the final R = 0.0337 and wR = 0.0644. In this complex, four carboxylates are bidentate- or chelate-coordinated with the Cd(II) centers to give the dinuclear structure. The other coordination positions of Cd(II) are occupied by the lone pair electrons from N of four pyridines. Thermal analyses DSC and TG-DTG have been used to determine the thermal decomposition mechanism of the title complex.