Synthesis,Structure and Luminescent Properties of a Two-dimensional Cobalt(Ⅱ) Coordination Polymer Based on 2-Thiobarbituric Acid

A two-dimensional coordination polymer Co(H_2tba)_2(DMF)_2]_n 1(H_2tba = 2-thiobarbituric acid anion, DMF = N,N-dimethylformamide) has been synthesized by Co Cl2·6H2O with the 2-thiobarbituric acid ligands under solvothermal conditions. Compound 1 was further characterized by FTIR, elemental analysis, TGA and powder XRD techniques. Single-crystal X-ray diffraction studies revealed that the title compound crystallizes in the monoclinic space group Pbca with a = 12.5948(12), b = 11.4269(11), c = 14.8939(15) ?, V = 2143.5(4) ?~3, Z = 4, Dc = 1.523 g·cm-3, F(000) = 1012, μ = 1.038 mm~(-1), R = 0.0358 and w R2 = 0.0888(I 2σ(I)). Single-crystal X-ray diffraction analysis reveals that 1 is the first two-dimensional noninterpenetrating(4, 4) net coordination polymer based on the 2-thiobarbituric acid. Coordination polymer 1 exhibits two luminescent emission spectra at 477 and 489 nm with the excitation peak at 273 nm.