Elastic properties of LaNiO$_{3}$ from first-principles calculations

TL;DR

This study uses first-principles density functional theory to comprehensively analyze the elastic and mechanical properties of LaNiO₃ across various phases, providing valuable theoretical insights into its behavior.

Contribution

It offers the first detailed theoretical investigation of LaNiO₃'s elastic properties across multiple phases using optimized DFT approaches.

Findings

Calculated elastic constants and mechanical stability for different phases.

Derived polycrystalline elastic moduli and related properties.

Provided theoretical data on LaNiO₃'s elastic and mechanical behavior.

Abstract

By applying density functional theory (DFT) approximations, we present a first-principles investigation of elastic properties for the experimentally verified phases of a metallic perovskite LaNiO$_{3}$. In order to improve the accuracy of calculations, at first we select the most appropriate DFT approaches according to their performance in reproducing the low-temperature crystalline structure and the electronic density of states observed for the bulk LaNiO$_{3}$. Then, we continue with the single-crystal elastic constants and mechanical stability for the most common rhombohedral as well as high-temperature cubic and strain-induced monoclinic phases. Together with the calculated single-crystal elastic constants, the deduced polycrystalline properties, including bulk, shear, and Young's moduli, Poisson's ratio, Vickers hardness, sound velocities, Debye temperature, and anisotropy indexes, remedy the existing gap of knowledge about the elastic and mechanical behaviour of LaNiO$_{3}$, at least from a theoretical standpoint.