Materials (Sep 2021)

First Principles Calculations of Atomic and Electronic Structure of <inline-formula><math display="inline"><semantics><mrow><msubsup><mi>Ti</mi><mi>Al</mi><mrow><mn>3</mn><mo>+</mo></mrow></msubsup></mrow></semantics></math></inline-formula>- and <inline-formula><math display="inline"><semantics><mrow><msubsup><mi>Ti</mi><mi>Al</mi><mrow><mn>2</mn><mo>+</mo></mrow></msubsup></mrow></semantics></math></inline-formula>-Doped YAlO<sub>3</sub>

  • Sergei Piskunov,
  • Aleksejs Gopejenko,
  • Vladimir Pankratov,
  • Inta Isakoviča,
  • Chong-Geng Ma,
  • Mikhail G. Brik,
  • Michal Piasecki,
  • Anatoli I. Popov

DOI
https://doi.org/10.3390/ma14195589
Journal volume & issue
Vol. 14, no. 19
p. 5589

Abstract

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In this paper, the density functional theory accompanied with linear combination of atomic orbitals (LCAO) method is applied to study the atomic and electronic structure of the Ti3+ and Ti2+ ions substituted for the host Al atom in orthorhombic Pbnm bulk YAlO3 crystals. The disordered crystalline structure of YAlO3 was modelled in a large supercell containing 160 atoms, allowing simulation of a substitutional dopant with a concentration of about 3%. In the case of the Ti2+-doped YAlO3, compensated F-center (oxygen vacancy with two trapped electrons) is inserted close to the Ti to make the unit cell neutral. Changes of the interatomic distances and angles between the chemical bonds in the defect-containing lattices were analyzed and quantified. The positions of various defect levels in the host band gap were determined.

Keywords