Magnetic and electronic structure studies of Mn1+xFe 2-2xTixO4 (0 ≤ x ≤ 0.5) ferrites

Abstract

A series of polycrystalline bulk samples of Mn1+xFe 2-2xTixO4 (0 ≤ x ≤ 0.5) have been prepared by using a conventional solid-state reaction method. The effect of Ti4+ ions substitution on magnetic and electronic structure of MnFe2O4 has been studied using isothermal d.c. magnetization and near edge X-ray absorption fine structure spectroscopy (NEXAFS) measurements. The magnetization studies infer that all samples have ferrimagnetic ordering at room temperature. The magneton number (nB) calculated using the magnetic hysteresis loop has been found to decrease linearly with the Ti substitution, which indicates that the system follows the Neel's two sub-lattice model. The decrease in the value of nB may be due to the dilution of the sub-lattice by Ti ions. The NEXAFS measurements performed at Fe/Ti L3, 2 edges indicate that Fe ions are in mixed valence state whereas Ti ions remain unchanged at 4+ state. © 2010 World Scientific Publishing Company.