Synthesis, structure, spectra and magnetic properties of the unsymmetrical oxo-bridged complex [Fe2O(OAsPh3)4Cl3] 2[Fe2OCl6].2CH3CN

Article abstract of DOI:10.1016/S0277-5387(98)00094-1

A new unsymmetrical (μ-oxo)diiron(III) complex [Fe₂O(OAsPh₃)₄Cl₃] ₂[Fe₂OCl₆].2CH₃CN (I), where OAsPh₃ is triphenylarsine oxide, has been prepared by several ways and characterized by X-ray structural analysis, elemental analysis, spectral and magnetic methods. The complex (I) is formed simultaneously with another two complexes of the composition [Fe₂O(OAsPh₃)₄Cl₃][FeCl ₄].CH₃CN (II) and [Fe(OAsPh₃)₄Cl₂] [ FeCl₄] (III). In compound (I) the complex cation has one Fe atom coordinated by four OAsPh₃ which form a plane, and the oxo-bridged ligand occupies an apex and form a square pyramid configuration about the second iron atom. In the complex anion each Fe atom is tetrahedrally coordinated by three chlorine atoms and the oxo bridge. The magnetic properties have been investigated in the 4.2-300 K temperature range and these data correspond to the EPR spectra.