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)(H2O)(2)](H2O)(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 diffiaction, 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) angstrom, beta = 90.5190(10)degrees, V = 2377.9(5) angstrom(3), Z = 2, C48H36Co3N8O20, M-r = 1221.64, D-c = 1.706 g/cm(3), F(000) = 1242 and mu(MoK alpha) = 1.128 mm(-1). The final R = 0.0497 and wR = 0.1461 for 4185 observed reflections with I > 2 sigma(I) and R = 0.0721 and wR = 0.1619 for all data. X-ray diffiaction 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.