EPR of substitutional and of charge compensated Fe3+ in anatase (TiO2) and its temperature dependence

• Main Author: Horn, Manfred
• Language: English
• Published: University of British Columbia 2011
• Subjects: Titanium dioxide; Electron paramagnetic resonance; Crystallography
• Online Access: http://hdl.handle.net/2429/33812

Paramagnetic resonances were observed in natural single crystals of anatase between 1 °K and 1230 °K and are interpreted as due to regular substitutional Fe(3+) (I) and to Fe (3+) combined with an oxygen vacancy at a nearest neighbour site (II) . The spin Hamiltonian parameter b(2)° of (I) decreases from +457 x 10(-4) cm(-1) at 1 °K almost linearly to -225 x 10(-4) cm(-1) at 1230 °K. This unusually strong temperature dependence of b(2)° and the observed temperature dependence of the orientation of the magnetic axes of spectrum (II) are both explained by assuming that the positions of the oxygen ions within the unit cell are temperature dependent. === Science, Faculty of === Physics and Astronomy, Department of === Graduate