Analysis of Correlation between Density Variations and Defect Structure of W6+ : LiTaO3

  • M. Tahiri Univ. Hassan 2, Laboratory of LBGIM, Research Team-Nanomaterial’s Physics
  • A. Jennane Univ. Hassan 1, Laboratry of RM&I, Research Team-Matter Physics and Modeling, Faculty of Sciences and Technics
  • N. Masaif Univ. Ibn Tofail, Physics Department, Faculty of Sciences
  • E. M. Lemdek Univ. CD E2M-LCCA, Chemistry Department, Faculty of Sciences
  • E. M. Lotfi Univ. Mohammed V-Souissi, Department of Mechanical Engineering
Keywords: LiTaO3, WO3, density, vacancy model, stoichiometry


We investigate the defect structure of non-stoichiometric solid solutions of WO3-doped LiTaO3 in correlation with the evolution of the density within our theoretical approach. The dopant concentration and the mechanism of substitution, which depends of the ionic rays of different cations that exit into the network, have an effect on crystalline parameters and, consequently, on the density. In order to explain the defect structure of solid solutions synthesized in the ternary system Li2O–Ta2O5–(WO3)2 in a vicinity of LiTaO3,, we have shown a convergence between theoretical and experimental results by the application of our theoretical approach combined with the new proposed vacancy models. We conclude that the new vacancy models are able to describe the defect structure and the substitution mechanism in each solid solutions of WO3-doped lithium tantalate.


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How to Cite
Tahiri, M., Jennane, A., Masaif, N., Lemdek, E., & Lotfi, E. (2018). Analysis of Correlation between Density Variations and Defect Structure of W6+ : LiTaO3. Ukrainian Journal of Physics, 63(4), 347.
Physics of magnetic phenomena and physics of ferroics