Calculated high-pressure structural properties, lattice dynamics and quasi particle band structures of perovskite fluorides KZnF 3 , CsCaF 3 and BaLiF 3

TL;DR

This study uses density functional theory to analyze high-pressure structural, lattice dynamic, and electronic properties of perovskite fluorides KZnF3, CsCaF3, and BaLiF3, confirming experimental data and highlighting the importance of quasiparticle corrections.

Contribution

It provides detailed theoretical insights into the structural and electronic properties of these fluorides under high pressure, with improved band gap predictions using quasiparticle calculations.

Findings

Structural properties agree with experimental data.

Phonon dispersion matches neutron scattering results.

Band gaps are larger with quasiparticle corrections.

Abstract

A detailed study of the high-pressure structural properties, lattice dynamics and band structures of perovskite structured fluorides KZnF3, CsCaF3 and BaLiF3 has been carried out by means of density functional theory. The calculated structural properties including elastic constants and equation of state agree well with available experimental information. The phonon dispersion curves are in good agreement with available experimental inelastic neutron scattering data. The electronic structures of these fluorides have been calculated using the quasi particle self-consistent [Formula: see text] approximation. The [Formula: see text] calculations reveal that all the fluorides studied are wide band gap insulators, and the band gaps are significantly larger than those obtained by the standard local density approximation, thus emphasizing the importance of quasi particle corrections in perovskite fluorides.