Publication date: Jul 12, 2021
This work details how to determine structural prototypes for the cubic perovskite structure that are used to study the B-site displacements in the cubic, paraelectric phase. Car-Parrinello MD simulations of cubic barium titanate (BaTiO3) show the titanium displacements from the undistorted cubic structure. Using a systematic symmetry analysis we construct microscopic templates, i.e. representative structural models in the form of supercells that satisfy a desired point symmetry but are built from the combination of lower-symmetry primitive cells. Density functional theory calculations, using the microscopic templates as starting structures for a relaxation, are carried out to find structural prototypes of BaTiO3 with local polar distortions but with cubic point symmetry. The stability of these structures is studied as a function of volume and with respect to the zone-boundary phonons of pristine cubic BaTiO3. The stable distortions patterns for BaTiO3 are investigated for other titanates and for a handful of niobates and zirconates.
No Explore or Discover sections associated with this archive record.
File name | Size | Description |
---|---|---|
README.txt
MD5md5:d990eba789b18b991aad5cba38edffee
|
1.1 KiB | Description of 'Figures_main', 'Figures_SI', 'microscopic_templates', 'materials_displacements', 'materials_5atom_phonon' and 'pseudopotenials' |
Figures_main.zip
MD5md5:3d961798e928c68d74e87cc97a048729
|
314.6 MiB | Contains directories with a brief README and the data to reproduce the figures in the main text, or directions to the relevant directory |
Figures_SI.tar.gz
MD5md5:d5de060f9d447b88d4ef8a2c60b1866f
|
239.1 MiB | Contains directories with a brief README and the data to reproduce the figures in the supplemental, or directions to the relevant directory |
microscopic_templates.tar.gz
MD5md5:f0ed9c7b434b933dc4124f3100f8216b
|
8.6 KiB | Contains a cif for a representation of each of the 27 distinct cubic microscopic templates of spacegroup 221 with occupied Wyckoff positions: 1a, 1b, 3c. In this representation BaTiO3 is used where Ba occupies the 1a, Ti the 1b, and O the 3c Wyckoff position in the high-symmetry phase. |
materials_displacements.zip
MD5md5:de1207ab0f532282f4733e8d039ad45d
|
18.2 MiB | his directory contains the output of the pw.x relax calculations of the 4+4 and 2+6 displacement patterns with fixed lattice parameters. |
materials_5atom_phonons.zip
MD5md5:785730b6237f72e7297577ad43498877
|
8.4 MiB | This directory contains the phonon calculations for the 5 atom cubic structures |
pseudopotentials.zip
MD5md5:ff653596767e303f7f23ba228810a2c7
|
27.2 MiB | contains the pseudopotentials used in the calculations |
2022.32 (version v2) | Feb 22, 2022 | DOI10.24435/materialscloud:jc-ky |
2021.104 (version v1) [This version] | Jul 12, 2021 | DOI10.24435/materialscloud:pg-50 |