Effect of substituting of S for O: The sulfide perovskiteBaZrS3investigated with density functional theory

Abstract

We use first-principles density functional theory calculations to investigate the ground-state structure of sulfide perovskite ${\text{BaZrS}}_{3}$. The material has a lower band gap than its oxide analog ${\text{BaZrO}}_{3}$. Neither are ferroelectric in the ground state at $T=0\text{ }\text{K}$. We also examine the IR-active phonon contributions to the dielectric constant $ϵ$ of ${\text{BaZrS}}_{3}$, which are then compared to those of ${\text{BaZrO}}_{3}$. The roles of atomic size, mass, and covalency are discussed with regard to band gap and dielectric response.