Atomistic Simulation of Structural and Mechanical Properties of the AMgF3 (A = K, Rb, and Cs) Compounds Under Hydrostatic Pressure.

Abstract

Structural, mechanical, elastic, and dielectric properties of the AMgF3 (A = K, Rb, and Cs) compounds were investigated using classical atomistic simulation. A new set of interatomic potentials was developed for these compounds. Lattice parameters and interatomic distances have shown to accurately reproduce all structures, with very close agreement to the experimental data. In all cases, the relative error is below 0.5%. Effect of hydrostatic pressure in the structural, mechanical, elastic, and dielectric properties of these materials were studied from 0 up to 50 GPa. Compounds behavior and stability under pressure were analyzed. KMgF3 and RbMgF3 changed from brittle to ductile at approximately 2 GPa. These calculations play an important role in understanding the properties of the AMgF3 (A = K, Rb, and Cs) compounds under pressure, and open up a new opportunity to study defects in this class of materials. © 2019 Wiley Periodicals, Inc.