Synthesis, structural analysis and magnetic properties of two novel doubly oxygen bridged binuclear manganese(III) and copper(II) complexes with ONO tridentate ligands

Abstract

Two novel binuclear Mn(III) [C22H26Cl4Mn2N2O6] (1) and Cu(II) [C26H14Cl4Cu2N2O4] (2) Schiff base complexes have been synthesized and their crystal structures have been determined by single crystal X-ray diffraction analysis. Structural analysis of (1) and (2) shows that the Schiff base ligand of dimers coordinates toward one metal atom in a tridentate mode and each Mn atom is six-coordinated while each Cu atom is four-coordinated. The two halves of the dimers are related by a crystallographic inversion center. The intramolecular non-bonding Mn center dot center dot center dot Mn separation is 2.994 angstrom for complex (1) and Cu center dot center dot center dot Cu separation is 2.994 angstrom for complex (2). Magnetic susceptibilities for (1) and (2) in the solid state have been measured over the temperature range 2-350 K as a function of temperature and the magnetic parameters have been determined with fitting procedure. Magnetic measurements on (1) and (2) reveal the presence of antiferromagnetic spin-exchange interactions between the transition metal ions.