Synthesis,Structure,and Magnetic Property of One Novel Entangled Cobalt~Ⅱ-organic Compound

One novel entangled cobalt compound,{Co 3 (nbta) 2 (4,4-bpy) 2 (H 2 O) 2 ](H 2 O) 2 } n (1,H 3 nbta=5-nitro-1,2,3-benzenetricarboxylic acid,4,4-bpy=4,4-bipyridyl),was prepared and characterized by X-ray diffraction,magnetism,elemental analysis,XPS,TGA and IR spectroscopy.The crystal of 1 crystallizes in monoclinic,space group Pc with a=13.0717(16),b=11.4167(14),c=15.9342(19),β=90.5190(10)o,V=2377.9(5)3,Z=2,C 48 H 36 Co 3 N 8 O 20,M r=1221.64,D c=1.706 g/cm 3,F(000)=1242 and μ(MoKα)=1.128 mm-1.The final R=0.0497 and wR=0.1461 for 4185 observed reflections with I > 2σ(I) and R=0.0721 and wR=0.1619 for all data.X-ray diffraction analyses revealed that Co(1) is linked by the nbta 3-ligands to form the ladder shape along the c axis,which is further extended into two-dimensional networks via the joint of Co(2) along the a axis.Moreover,these two dimensional motifs are interconnected by the 4,4-bpy bridges to form a complicated 3-D polymeric framework.Magnetic measurements revealed that compound 1 shows strong antiferromagnetic property.