Synthesis,Crystal Structure and Characterization of a New Coordination Polymer from the Self-assembly of CoCl2 Salt and Flexible Ligand 1,3-Bis（4-pyridyl）propane

A new 1D coordination polymer [Co(bpp)3Cl2(H2O)2]n 1 (bpp = 1,3-bis(4-pyridyl)-propane) was synthesized and characterized by elemental analysis,IR spectrum and single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system,space group Ibca with a = 16.569(9),b = 17.240(10),c = 27.087(16) ,V = 7738(8) 3,Z = 8,Dc = 1.306 g/cm3,Mr = 760.65,λ(MoKa) = 0.71073 ,μ = 0.623 mm1,F(000) = 3192,the final R = 0.0678 and wR = 0.2011. The Co(II) atom is coordinated in a slightly distorted octahedral CoN4Cl2 geometry by two Cl atoms in the axial positions,four N atoms from the two bridging bpp ligands and two pendant bpp ligands. The CoN4Cl2 octahedra are connected by the bridging bpp ligands to form a 1D neutral coordination polymer chain. The chains are linked by face-to-face π-π interactions between adjacent pendant bpp ligands to give rise to a 3D supramolecular architecture. The photoluminescent investigation indicates that the emission of 1 is attributed to ligand-centered emission. The variable-temperature magnetic susceptibility measurement shows weak antiferromagnetic behavior in the complex.