Investigations On The Local Structure And G Factors For The Interstitial Ti~(3+) In Tio_2

摘要

The EPR g factors gi (i = x, y, z) for the interstitial Ti~(3+) in rutile are theoretically studied from the perturbation formulas of these parameters for a 3d~1 ion in rhombically compressed octahedra. The ligand octahedron in the impurity center is found to be less compressed than that on the host interstitial site due to the Jahn-Teller effect. The local compression parameter (≈0.026) and the rhombic distortion angle δφ' (≈0.7°) around the impurity Ti~(3+) are smaller than the host values (≈0.091 and 3.5°). The theoretical g factors based on the above local structural parameters are in good agreement with the experimental data. In addition, the g factors for a tetragonal interstitial Ti~(3+) center are also reasonably interpreted.