Synthesis,Crystal Structure and Fluorescence Property of a New Trinuclear Nickel(Ⅱ) Complex Bridged by 2,6-Pyridine Dicarboxylic Acid

A new trinuclear nickel complex,[Ni3(pdc)3(2,2’-bipy)3(H2O)2]·2H2O(H2pdc = pyridine 2,6-dicarboxylic acid,2,2’-bipy = 2,2’-bipyridine) has been hydrothermally synthesized and characterized by IR,elemental analysis and X-ray diffraction methods.Crystal data for this complex:monoclinic,space group P21/n,a = 21.206(4),b = 10.002(2),c = 28.066(6),β = 108.18(3)°,C51H41N9Ni3O16,Mr = 1212.06,V = 5.656(2) nm3,Dc = 1.423 g·cm-3,μ(MoKα) = 1.062 mm-1,Z = 4,F(000) = 2488,GOOF = 1.034,the final R = 0.0543 and wR = 0.1237 for 6149 observed reflections with Ⅰ > 2σ(Ⅰ).In the complex,three nickel(Ⅱ) ions are bridged by the pyridine 2,6-dicarboxylic acid groups,and all nickel(Ⅱ) ions are seven-coordinated by nitrogen atoms of 2,2’-bipyridine and pyridine 2,6-dicarboxylic acid and oxygen atoms from pyridine 2,6-dicarboxylic and water to adopt a severely distorted pentagonal bipyramidal geometry.The emission and excitation peaks of the complex in ethanol solutions are located at 336 and 316 nm,respectively.