Structural, Magnetic and Mössbauer Studies of the Mixed- Metal Molecular Ferromagnet Compounds NBu₄[MCr(C₂O₄)3] (Bu═(CH₂)₃CH₃, M═Mn, Fe)

Abstract

Abstract An X-ray study of a single crystal of the NBu4[MnCr(C2O4)3 composition reveals a layered structure with an ordered arrangement of Mn2+ and Cr3+ ions. According to the data of the orientation dependence of magnetization at 4.5 K, the magnetic easy axis is aligned along the crystal c-axis. Mössbauer data analysis of isostructural NBu4[FeCr(C2O4)3] powdered material gives, on the contrary, the evidence of strong confinement of Fe2+ spins to the crystal basal plane. The ferromagnetic system which arises here is a quasi-2D system in terms of the nature of its exchange interactions.