6533b86dfe1ef96bd12c9438
RESEARCH PRODUCT
Phonon calculations in cubic and tetragonal phases of SrTiO3: A comparative LCAO and plane-wave study
Evgeny BlokhinEugene A. KotominEugene A. KotominD. GryaznovD. GryaznovJoachim MaierRobert A. Evarestovsubject
Brillouin zonePhysicsCondensed Matter::Materials ScienceTetragonal crystal systemTight bindingCondensed matter physicsPhononLinear combination of atomic orbitalsPlane waveAb initioCondensed Matter PhysicsHeat capacityElectronic Optical and Magnetic Materialsdescription
The atomic, electronic structure and phonon frequencies have been calculated in cubic and low-temperature tetragonal SrTiO${}_{3}$ phases at the ab initio level. We demonstrate that the use of the hybrid exchange-correlation PBE0 functional gives the best agreement with experimental data. The results for the standard generalized gradient approximation (PBE) and hybrid PBE0 functionals are compared for the two types of approaches: a linear combination of atomic orbitals (CRYSTAL09 computer code) and plane waves (VASP5.2 code). The relation between cubic and tetragonal phases and the relevant antiferrodistortive phase transition is discussed in terms of group theory and is illustrated with analysis of calculated soft-mode frequencies at the \ensuremath{\Gamma} and $R$ points in the Brillouin zone. Based on phonon calculations, the temperature dependence of the heat capacity is in good agreement with experiment.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-04-08 | Physical Review B |