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 represents N, N'-bis(3-aminopropyl) oxam-ido. Based on 1R, elemental analysis, conductivity measurement and electronic spectra, these complexes were characterized by an extended oxamido-bridged structure with Cu(Ⅱ) in a planar environment and Co(Ⅱ) in a octahedral environment. The symmetry of the cation is very close to C_2v.The complexes were also characterized with variable temperature (4～300K) magnetic susceptibility, and the data were fit for the susceptibility equation derived from spin Hamilton, H= -2JS₁·S₂-DS_x1² by least square strategy. The exchange integral, J, was found to be -22.36cm^-1 (for bpy);-15.45cm^-1 (for phen); -19.10cm^-1(for NO₂-phen), indicating that there is a weak antiferromagnetic spin-exchange interaction between the metal ions.

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