2005/03/31 by V I Anisimov, V. I. Anisimov, M. A. Korotin +11 · 1 citation
Energy · Materials Science · Physics and Astronomy · #Magnetic and transport properties of perovskites and related materials #TiO2 Photocatalysis and Solar Cells #ZnO doping and properties #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1088/0953-8984/18/5/022
published as J. Phys.: Condens. Matter 18, N 5 (2006) 1695-1704
openalex publication_date 2006/01/18 · arxiv created 2006/01/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We have investigated the role of transition metal impurities and oxygen vacancies in the formation of ferromagnetism in Co-doped TiO 2 using the LSDA + U approach which takes into account strong on-site Coulomb correlations for electronic structure calculations. Several model supercells of rutile TiO 2 , with a Co 2+ ion in high-spin state substituted into the titanium site and with oxygen vacancies, were considered. We found that the exchange interaction of Co magnetic ions is ferromagnetic, but very weak due to the large average impurity–impurity distance. However, it becomes three times stronger when there is a magnetic vacancy nearby. The magnetic moment values are 3 μ B for Co 2+ and −1 μ B for vacancy. Our investigation showed that the exchange interaction energy of Co and vacancy moments varies from 330 to 40 meV depending on the distance between them in the supercell. We assume that the strong interaction between Co and vacancy moments should be taken into account to explain the high Curie temperature value in Co-doped TiO 2 .