Abstract: Three heterobinuclear complexes were synthesized, namely Cu(oxpn)Co(L)₂(ClO₄)₂·xH₂O (L=2,2'-bipyridyl (bpy), 1, 10-phenanthroline (phen), and 5-nitro-1,10-phenanthroline (NO₂-phen), where oxpn is N, N'-bis(3-aminopropyl)oxamido. Based on IR, elemental analyses, conductivity measurement and electronic spectra these complexes are proposed to have extended oxamido-bridged structure and to consist of Cu(Ⅱ) in a planar environment and Co(Ⅱ) in an octahedral environment. The cation symmetry is very close to C_2v. The complexes were characterized with variable temparaturo magnetic susceptibility (4～300K) and the data were fitted with the least-square to the susceptibility equation derived from spin Hamilton,.The exchange integral, J, was found to be -22.36 cm^-1(for bpy); -15.45 cm^-1(for phen);-19.10 cm^-1(for NO₂-phen), indicating that a weak antiferromagnetic spin-exchange interacts between the metal ions.

Key words: Oxamido-bridge, Copper(Ⅱ)-cobalt(Ⅱ), Magnetism