Synthesis, Crystal Structure and Theoretical Calculations of a Three-dimensional Supramolecular Cadmium(Ⅱ) Coordination Polymer

摘要

A new metal-organic cadmium coordination polymer [Cd(pzdc)0.5(L)]n·nH2O (1,H2pzdc =pyrazine-2,3-dicarboxylic acid,HL =3-(2-pyridyl)pyrazole) has been successfully synthesized under hydrothermal conditions.The structure has been determined by single-crystal X-ray diffraction analysis,elemental analyses,IR and fluorescence spectrum.Brown crystals crystallize in the orthorhombic system,space group Fdd2 with a =1 1.2636(9),b =38.296(3),c =10.5795(8) A,V=4563.5(6) A3,C11H9CdN4O3,Mr =357.62,Dc =2.082 g/cm3,μ(MoKa) =1.924 mm-1,F(000) =2800,Z =16,the final R =0.0169 and wR =0.0443 for 2106 observed reflections (I ＞ 2σ(I)).It shows a two-dimensional network structure and extends into a three-dimensional supramolecular framework through π-π stacking interactions.Moreover,we analyzed Natural Bond Orbital (NBO) by using the PBE0/LANL2DZ method built in Gaussian 03 Program.The calculation results showed obvious covalent interaction between the coordinated atoms and Cd(Ⅱ) ion.