Generation of low-symmetry perovskite structures for ab initio computation

TL;DR

This paper introduces a computer program that simplifies the generation of low-symmetry perovskite structures, including ion displacements and octahedral tilting, to aid ab initio computational studies of their properties.

Contribution

A novel software tool for efficiently creating complex, distorted perovskite structures for ab initio calculations, addressing challenges in modeling multiple structural phases.

Findings

Facilitates rapid generation of low-symmetry perovskite structures

Enables detailed ab initio studies of structural phase interactions

Reduces computational preparation time for large supercells

Abstract

Ion displacements are the cause of the ferroelectricity in perovskites. By properly shifting ions, ab initio computations have been extensively used to investigate properties of perovsites in various structural phases. In addition to the relatively simple ion displacements, perovskites have another type of structural distortion known as antiferrodistortion or oxygen octahedron tilting. The interplay between these two types of distortions have generated abundant structural phases that can be tedious to prepare for ab initio computation, especially for large supercells. Here, we design and implement a computer program to facilitate the generation of distorted perovskite structures, which can be readily used for ab initio computation to gain further insight into the perovskite of a given structural phase.