Mِssbauer study and magnetic properties of Ti0.99 57Fe0.01O2

Mössbauer spectra of Ti0.99 57Fe0.01O2 prepared with 57Fe enriched iron have been taken at various temperatures ranging from 80 to 300 K. The Mössbauer spectrum of Ti0.99 57Fe0.01O2 consists of a ferromagnetic (six-Lorentzian) and a paramagnetic phase (doublet) over all temperature ranges. Isomer shifts indicate Fe2+ for the ferromagnetic phase, but Fe3+ for the paramagnetic phase of Ti0.99 57Fe0.01O2 sample. It is noted that the magnetic hyperfine field of ferromagnetic phase had the value about 1.5 times as large as that of α-Fe. The XRD data for Ti0.99 57Fe0.01O2 showed a pure rutile phase with tetragonal structures without any segregation of Fe into particulates within the instrumental resolution limit. The magnetic hysteresis (M–H) curve at room temperature showed an obvious ferromagnetic behavior and the magnetic moment per Fe atom under the applied field of 1 T was estimated to be about 0.68 μB, suggesting a low spin configuration of Fe ions.