Quantum mechanical method for estimating ionicity of spinel ferrites

The ionicity (0.879) of cubic spinel ferrite Fe3O4 has been determined, using both experimental magnetization and density of state calculations from the density functional theory. Furthermore, a quantum mechanical estimation method for the ionicity of spinel ferrites is proposed by comparing the results from Phillips' ionicity. On the basis of this, ionicities of the spinel ferrites MFe2O4 (M=Mn, Fe, Co, Ni, Cu) are calculated. As an application, the ion distribution at (A) and [B] sites of (A)[B](2)O(0)4 spinel ferrites MFe2O4 (M=Fe, Co, Ni, Cu) are calculated using current ionicity values. (C) 2012 Elsevier B.V. All rights reserved.