First Principles Calculations of Atomic and Electronic Structure of TiAl3+- and TiAl2+-Doped YAlO3

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

doi:10.3390/ma14195589

First Principles Calculations of Atomic and Electronic Structure of TiAl3+- and TiAl2+-Doped YAlO₃

Materials (Basel). 2021 Sep 26;14(19):5589. doi: 10.3390/ma14195589.

Authors

Sergei Piskunov¹, Aleksejs Gopejenko¹, Vladimir Pankratov¹, Inta Isakoviča¹, Chong-Geng Ma², Mikhail G Brik^{2

3

4}, Michal Piasecki^{5

6}, Anatoli I Popov¹

Affiliations

¹ Institute of Solid State Physics, University of Latvia, Kengaraga Street 8, LV-1063 Riga, Latvia.
² College of Sciences & CQUPT-BUL Innovation Institute, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
³ Institute of Physics, University of Tartu, W. Ostwald Str. 1, 50411 Tartu, Estonia.
⁴ Academy of Romanian Scientists, Ilfov Str. No. 3, 050044 Bucharest, Romania.
⁵ Faculty of Science and Technology, Jan Długosz University, Armii Krajowej 13/15, PL-42200 Częstochowa, Poland.
⁶ Department of Inorganic Chemistry, Uzhhorod National University, 46 Pidhirna Str., 88000 Uzhhorod, Ukraine.

Abstract

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: Ti-dopant; YAlO3; ab initio modelling; electronic structure; substitutional point defects.

Grants and funding

LZP-2018/1-0214/Latvijas Zinātnes Padome