The relationship between magnetic behaviour and local structure around Fe ions in Fe-doped TiO(2) rutile

• Published in: Physica. B, Condensed matter Condensed matter, 2009-10, Vol.404 (18), p.2838-2840
• Main Authors: Navarro, A.M. Mudarra, Bilovol, V, Cabrera, A F, Torres, C.E. Rodriguez, Sanchez, F H
• Format: Article
• Language: English
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2009.06.098

The magnetic and structural characterization of Ti(1-)(x))Fe(x))O(2) (x=0.025, 0.05, 0.07, 0.125, and 0.15) samples prepared by mechano-synthesis using TiO(2) and Fe(2)O(3) as starting materials are reported. XANES measurements performed at the Fe K-edge show that Fe ions are in 3+ oxidation state in the 7 at% Fe-doped sample and in a mixture of 2+ and 3+ oxidation states in the other samples. EXAFS results show the incorporation of Fe ions substituting Ti ones in the rutile TiO(2) structure. They also reveal a strong correlation between the number of oxygen nearest neighbours and the Fe(2+) fraction, i.e the number of oxygen near neighbours decreases when the Fe(2+) fraction increases. All samples present ferromagnetic-like behaviour at room temperature. We found a clear dependence between saturation magnetization and coercivity with the fraction of Fe(2+) and/or the number of Fe near neighbour oxygen vacancies.