Magnetic Anomaly in FeTiO3-αFe2O3 System by Mössbauer Effect

Abstract

The solid solutions $\mathrm{}(1-x)\mathrm{}\mathrm{FeTi}{\mathrm{O}}_3-x{\mathrm{Fe}}_2{\mathrm{O}}_3$ exhibit strong ferrimagnetic moments for the compositions $x<\mathrm{}0.6\mathrm{}$, where the Fe and Ti ions are ordered in the alternate (111) layers. The anomaly revealed by the Mössbauer measurements is that the ferrimagnetic phase consists of ferrimagnetic clusters surrounded by paramagnetic media. The size of these clusters decreases with increasing temperature or increasing local concentration of Ti. The isomer shift of FeTi${\mathrm{O}}_3$ is 1.2 mm/sec at room temperature as expected for ${\mathrm{Fe}}^{2+}$, although the quadrupole splitting of 0.62 mm/sec is smaller than that observed in other ferrous environments.