Hybrid density functional theory calculations on phonons in LaCoO3

TL;DR

This study uses hybrid density functional theory to calculate phonon frequencies in LaCoO3, comparing two computational approaches and validating results against experimental data, demonstrating the effectiveness of PBE0 in predicting phonon properties.

Contribution

It provides a comparative analysis of plane wave and LCAO methods for phonon calculations in LaCoO3 using hybrid DFT, confirming PBE0's accuracy.

Findings

Good qualitative agreement between methods

Quantitative accuracy within 30% margin

Theoretical results align with experimental data

Abstract

Phonon frequencies at Gamma-point in non-magnetic rhombohedral phase of LaCoO3 were calculated using density functional theory (DFT) with hybrid exchange correlation functional PBE0. The calculations involved a comparison of results for two types of basis functions commonly used in ab intiio calculations, namely the plane wave (PW) approach and linear combination of atomic orbitals (LCAO), as implemented in VASP and CRYSTAL computer codes, respectively. A good qualitative, but also within an error margin of less than 30%, a quantitative agreement was observed not only between the two formalisms but also between theoretical and experimental phonon frequency predictions. It is concluded that the hybrid PBE0 functional is able to predict correctly the phonon properties in LaCoO3.