Synthesis,Characterization and Magnetic Studies of Oxamido-Bridged Copper(II)-Iron(III) Heterobinuclear Complexes

摘要

Two new oxamido-bridged Cu(II)-Fe(III) heterobinuclear complexes of formulae [Cu(dmoxpn)Fc(bpy)_2](ClO_4)_3 (1) and fCu(dmoxae)Fc(bpy)_2](ClO_4)_3 (2) have been synthesized,where bpy denotes 2,2'-bipyridine;while dmoxpn and dmoxae represent N,N'-bis[3-(dimethylamino)propyl]oxamido and N,N'-bis[2-(dimethyl-amino)cthyl]oxamido dianions,respectively.Based on elemental analyses,molar conductivity measurements,IR and electronic spectral studies,it is proposed that the two complexes have oxamido-bridged structures consisting of a copper(II) and an iron(III) ions,which have a square planar environment and a distorted octahedral environment,respectively.The two heterobinuclear complexes were further characterized by variable-temperature magnetic susceptibility (4.2approx300 K) measurements and the observed data were simulated by the equation based on the spin Hamiltonian operator,H=-2JS_1S_2,giving the exchange integral J=-18.2 cm~(-1) for (1) and J=-26.5 cm~(-1) for (2).The results revealed the occurrence of an intramolecular antiferromagnetic interaction between the adjacent iron(III) and copper(II) ions through the oxamido--bridge within each molecule.The influence of the chclate ring arrangement around the copper(II) in the copper(II)-iron(III) heterobinuclear complexes on magnetic interactions between the metal ions of this kind of complexes is preliminarily discussed.