A New Cd(Ⅱ) Coordination Polymer Constructed by 3-(2-Pyridyl)pyrazole and 5-Nitroisophthalic Acid:Synthesis, Crystal Structure and Theoretical Calculations

摘要

A new coordination polymer,[Cd2(NIPH)(L)2(H2O)]n (1,HL =3-(2-pyridyl)pyrazole and H2NIPH =5-nitroisophthalic acid),has been synthesized.The structure of complex 1 has been characterized by X-ray single-crystal diffraction,elemental analysis,IR spectrum analysis,thermogravimetric analysis and fluorescence spectrum analysis.Complex 1 belongs to the triclinic system,space group P-1 with a =8.9539(6),b =11.6252(8),c =12.2472(8) A,a =80.011(2),β =80.3850(10),y =86.773(2)°,V =1237.37(14) A3,Z =2,Dc =1.987 g/cm3,μ =1.780 mm-1,Mr =740.25,F(000) =724,the fmal R =0.0295 and wR =0.1015 with 1 ＞ 2σ(I).Two H2NIPH as monodentate and bidentate ligands and two L ligands link four Cd(Ⅱ) ions to form a tetranuclear subunit.Each pair of the tetranuclear subunits is bridged by NIPH ligands to yield a one-dimensional double-chain structure.Furthermore,the 1D chains are linked into a 3D supramolecular framework with hydrogen bonds and π-π interactions.In addition,we analyzed Natural Bond Orbital (NBO) in using the PBE0/LANL2DZ method built in Gaussian 03 Program.The calculation results indicated the obvious covalent interaction between the coordinated atoms and Cd(Ⅱ) ion.