An old system revisited: Al₂O₃:Ti³⁺: Microscopic crystal field effects explored by the crystal field and first-principles calculations

X.-K. HU, B. WU, Y. YANG, Yau Yuen YEUNG, C.-G. MA, M.G. BRIK

Research output: Contribution to journalArticles

Abstract

The exchange charge model of crystal field has been used to analyze the microscopic crystal field in the Al₂O₃:Ti³⁺ system. The effects of lattice relaxation upon doping were treated in the framework of density functional based calculations of the optimized geometry of the doped host. The optimized Al₂O₃:Ti³⁺ structure was used as an input for the calculations of distance dependence of the crystal field parameters and crystal field splittings of the Ti³⁺ 3d states. From these calculations, the constants of the electron-vibrational interaction and the Stokes shift between the absorption and emission spectra of Ti³⁺ ions in Al₂O₃:Ti³⁺ were estimated to yield good agreement with the experimental results. In addition, four parameters of the superposition model of the crystal field (which in general are considered as the fitting parameters) were extracted from the results of the exchange charge model calculations. The proposed method of linking together two independent models of the crystal field is a reliable way of calculating the superposition model parameters (rather than allowing them to vary freely) and can be readily applied to other systems. Copyright © 2020 Elsevier B.V. All rights reserved.
Original languageEnglish
Article number156459
JournalJournal of Alloys and Compounds
Volume847
Early online dateJul 2020
DOIs
Publication statusE-pub ahead of print - Jul 2020

Citation

Hu, X.-K., Wu, B., Yang, Y., Yeung, Y. Y., Ma, C.-G., & Brik, M. G. (2020). An old system revisited: Al₂O₃:Ti³⁺: Microscopic crystal field effects explored by the crystal field and first-principles calculations. Journal of Alloys and Compounds, 847. Retrieved from https://doi.org/10.1016/j.jallcom.2020.156459

Keywords

  • Crystal field
  • Transition metal ion impurities
  • Optical properties
  • Electron-vibrational interaction

Fingerprint Dive into the research topics of 'An old system revisited: Al₂O₃:Ti³⁺: Microscopic crystal field effects explored by the crystal field and first-principles calculations'. Together they form a unique fingerprint.