Synthesis and characterization of μ-oxamido copper(Ⅱ)-iron(Ⅱ) heterobinuclear complexes with an antiferromagnetic exchange interaction

Four new u-oxamido heterobinuclear complexes have been synthesized and identified as Cu(oxap)Fe(L)2]SO4, where oxap denotes the N, N'-bis(2-aminopropyl)oxamido dianion and L represents diaminoethane (en); 1,3-diaminopropane (pn); 1,2-diaminopropane (ap) and 2,9-dimethyl-1,10-phenanthroline (Me2-phen). Based on the elemental analyses, spectroscopic studies, magnetic moments (at room temperature) and molar conductivity measurements, extended oxamido-bridged structures consisting of a copper(Ⅱ) and an iron(Ⅱ) ions, which have a square planar environment and an octahedral environment, respectively, are proposed for these complexes. Complexes Cu(oxap)Fe(en)2]SO4 (1) and Cu(oxap)Fe(pn)2]SO4 (2) have been characterized by variable temperature magnetic susceptibility (4.2~300 K) and the observed data were least-squares fitted to the susceptibility equation derived from the spin Hamiltonian including single-ion zero-field interaction for the iron(Ⅱ) ion, H=-2JS1.S2-DSzl2, giving the exchange integrals J=-2

Synthesis and characterization of μ-oxamido copper(II)-iron(II) heterobinuclear complexes with an antiferromagnetic exchange interaction

Four new μ-oxamido heterobinuclear complexes have been synthesized and identified as Cu(oxap)Fe(L)₂]SO₄, where oxap denotes the N, N'-bis(2-aminopropyl)oxamido dianion and L represents diaminoethane (en); 1,3-diaminopropane (pn); 1,2-diaminopropane (ap) and 2,9-dimethyl-l,10-phenanthroline (Me₂-phen). Based on the elemental analyses, spectroscopic studies, magnetic moments (at room temperature) and molar conductivity measurements, extended oxamido-bridged structures consisting of a copper(II) and an iron(II) ions, which have a square planar environment and an octahedral environment, respectively, are proposed for these complexes. Complexes Cu(oxap)Fe(en)₂]SO₄ (1) and Cu(oxap)Fe(pn)₂]SO₄ (2) have been characterized by variable temperature magnetic susceptibility (4.2～'300 K) and the observed data were least-squares fitted to the susceptibility equation derived from the spin Hamiltonian including single-ion aero-field interaction for the iron(II) ion, H=?2J?₁ ·;?₂—D?²_zl, giving the exchange integrals J=?21.9 cm^?1 for 1 and J=?23.6 cm^?1 for 2. These results are commensurate with antiferromagnetic interactions between adjacent metal ions within each molecule.