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Updated: Jul 7, 2026

Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Defect model and EPR parameters for the tetragonal Yb3+ center in KTaO3 crystal
Wen-Lin Feng1, Hong-Gang Liu, Wen-Chen Zheng
1Department of Material Science, Sichuan University, Chengdu 610064, PR China.
Abstract:
The defect model of the tetragonal Yb3+ (at K+ site) center in KTaO3 crystal is suggested, i.e., Yb3+ ion does not occupy the ideal K+ site, but is displaced by an amount DeltaZ along one of 100 axes because of the much smaller ionic radius of Yb3+ compared with that of the replaced K+. Based on the defect model, the EPR parameters (g factors g(parallel), g(perpendicular) and hyperfine structure constants 171A parallel, 171A perpendicular, 173A parallel, 173A perpendicular) are calculated by diagonalizing the 14 x 14 complete energy matrix. The calculated values are in agreement with the observed values and the off-center displacement DeltaZ (approximately 0.2 angstroms) is estimated from the calculations. These results are discussed.
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