| Abstract: A coordination polymer, namely [Ni(cpna)(bpy)(H2O)]n (1) has been constructed hydrothermally using H2cpna (H2cpna=5-(2′-carboxylphenyl) nicotic acid), bpy (bpy=2,2′-bipyridine) and Ni(OAc)2·4H2O. The complex crystallizes in the monoclinic system, space group P21/c with a=1.666(2) nm, b=0.962 2(12) nm, c=1.270 2(16) nm, β=105.978(12)°, V=1.957(4) nm3, Dc=1.608g·cm-3, Z=4, R=0.038 7 and wR=0.089 3 (I>2σ(I)). Three Ni(Ⅱ) atoms, three cpna ligands, three 2,2′-bpy ligands, and three water ligands form a [Ni3(cpna)3(bpy)3(H2O)3] ring. The rings are connected by the coordination interactions of cpna ligands and Ni(Ⅱ) ions to generate a 2D sheet, which are further extended into a 3D metal-organic supramolecular framework by π-π stacking interactions. Magnetic studies for complex 1 show a weak antiferromagnetic coupling between the nearest Ni(Ⅱ) centers, with g=2.10 and J=-0.87 cm-1. CCDC: 816351. |
