Synthesis and Magnetic Properties of μ-Phthalato Binuclear Cobalt(II) Complexes

Abstract

Abstract Three Co(II)-Co(II) binuclear complexes have been synthesized, namely [Co2(Phth)(H2O)(L)4](ClO4)2 [L = 2,2′-bipyridyl (bpy), 1,10-phenanthroline (phen) and 5-nitro-1,10-phenanthroline (NO2-phen)], where Phth2- is the dianion of phthalic acid. The complexes have been characterized by elemental analyses, conductivity measurements, electronic and IR spectra, and a crystal structure determination. They have extended Phth-bridged structures consisting of two cobalt(II) ions in a distorted octahedron environment. The temperature dependence of the magnetic susceptibility of [Co2(Phth)(H2O)(bpy)4](ClO4)2 and [Co2(Phth)(H2O)(phen)4](ClO4)2 ˙ H2O has been studied giving the exchange integral J = -1.04 cm−1 and J = -1.02 cm−1, respectively. This indicates a weak antiferromagnetic interaction between the metal ions.