Self-consistent hybrid functional calculations: Implications for structural, electronic, and optical properties of oxide semiconductors

TL;DR

This paper applies a new self-consistent hybrid functional within density functional theory to oxide semiconductors, achieving improved accuracy in structural and electronic property predictions with moderate computational cost.

Contribution

The study demonstrates the effectiveness of a recently developed self-consistent hybrid functional for accurately predicting properties of oxide semiconductors, surpassing traditional hybrid functionals in some cases.

Findings

Improved structural data agreement with experiments for all studied materials.

Enhanced electronic property predictions for ZnO and MgO.

Comparable or better results than PBE0 for structural and electronic properties.

Abstract

The development of new exchange-correlation functionals within density functional theory means that increasingly accurate information is accessible at moderate computational cost. Recently, a newly developed self-consistent hybrid functional has been proposed [Skone \textit{et al.} Phys. Rev. B \textbf{89}, 195112 (2014)], which allows for a reliable and accurate calculation of material properties using a fully \textit{ab initio} procedure. Here, we apply this new functional to wurtzite ZnO, rutile SnO$_2$, and rocksalt MgO. We present calculated structural, electronic, and optical properties, which we compare to results obtained with the PBE and PBE0 functionals. For all semiconductors considered here the self-consistent hybrid approach gives improved agreement with experimental structural data relative to the PBE0 hybrid functional for a moderate increase in computational cost, while avoiding the empiricism common to conventional hybrid functionals. The electronic properties are improved for ZnO and MgO, whereas for SnO$_2$ the PBE0 hybrid functional gives best agreement with experimental data.