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.

The Trivalent Rare‐Earth Dopant in the KBaPO4 and KSrPO4 Compounds: An Atomistic Simulation Study

“…Analyzing the experimental results reported and the recent works on other materials [ 29,31–38 ] indicates that the atomistic modeling technique works well. We use this technic for examining the relative energies of substitution of trivalent RE dopant at K, Ba/Sr, and P host sites in KMPO 4 , knowing that charge compensating mechanisms are needed and all possible schemes, using Kröger−Vink notation, [ 27 ] were considered, and are summarized and shown in Table 3 .…”

Defect clustering in an Eu-doped NaMgF3 compound and its influence on luminescent properties

“…The Na atom is coordinated by eight F atoms, with only two Na-F1 bonds, and almost all bond distances are between Na-F2. This compound presents a different structural behaviour at room temperature and pressure compared to other materials of the same family (AMgF 3 , A = Cs, Rb, and K) 33.…”

“…44 The empirical fitting was used to obtain Buckingham potential parameters for the Na−F interaction. The potential parameters used for Mg−F and F−F interactions were taken from a previous study 33 and have already been tested and validated for compounds of the same family, AMgF 3 (A = K, Cs, and Rb). Table 1 shows the interatomic potentials and shell model commonly used to synthesize NaMgF 3 .…”

“…In this methodology, interactions between atoms are determined by interatomic potentials that are essential to studying physical properties of the simulated systems. Several studies have been widely used to examine structural, mechanical, elastic, and dielectric properties in solid-state materials [32][33][34][35][36] . Furthermore, atomistic simulation is able to perform studies on defect properties with low computational cost, compared with other methodologies, and has been successfully employed to study defects.…”

Elucidating the effect of intrinsic defects on the dosimetric properties of the MgB4O7compound: an atomistic simulation approach

“…Several recently published studies have brought great advances in the analysis of materials using this computational methodology. [15][16][17][18][19] Also, computational methodologies of defect characterisation have brought important progress in areas of inorganic chemistry and materials science, through studies involving diffusion processes of ions in solids, 20,21 high-performance optical devices, 22,23 electrocatalysis, 24 among others. However, there is still a considerable gap in the chemistry of defects and their relationship with some mechanisms involved in ionizing radiation and scintillation dosimetry, for example, as well as their relationship with manufacturing technologies.…”