Existence of the β-tin structure in Sr: First evidence from computational approach

Abstract

Molecular Dynamics (MD) calculation is one of the most powerful theoretical methods widely used to predict and to confirm structural phase transitions. In this work, the MD method has been used to verify phase transition from body-centered cubic (bcc) to β-tin structure, then, to the Cmcm and hexagonal close-packed (hcp) structure, respectively. The transition sequence from previous theoretical works has been confirmed. In this study, Density Functional Theory (DFT), has been used to calculate phonon dispersion to confirm the stability of β-tin and hcp phases. The long time discrepancies in transition sequence between the calculation and the experimental works has been explained by conventional DFT calculation using screened exchange local density approximation (sX-LDA). More importantly, the existence of β-tin structure is finally predicted and the transition nature of Sr has also been revealed.

Bain Deformation Mechanism and Lifshitz Transition in Magnesium under High Pressure

“…The structural phase transitions in AEMs have been previously investigated. A theoretical study of Sr, [ 10 ] as indicated by the screened exchange local density approximation, was able to predict the transition nature of Sr and in turn reported agreement with experimental observations. Moreover, the structures in AEMs can be attributed to the possibility of being able to examine the stable structure through the energy of valence states.…”

Semiconducting phase of hafnium dioxide under high pressure: a theoretical studied by quasi-particle GW calculations

“…It should be noted that our calculations were performed at a temperature of 0 K, indicating that the enthalpy can confirm a phase stability under high pressure. [30,31,32,33,34,35,36,37] This is due to the fact that there is no entropy contribution. As a result, the relationship between pure elements Hf and O displayed the formation of HfO 2 .…”

Superconductivity in Materials under Extreme Conditions: An ab-initio Prediction from Density Functional Theory

“…For further details of the energy cutoff for plane waves and the Monkhorst-Pack k-point mesh as well as the DFT software have been described extensively in Refs. [10,[12][13][14]. Our works used the AIRSS technique, based on the density functional theory, to predict the novel structure.…”

“…However, the discrepancy between the experimental observations and the theoretical studies were not solved yet. In 2015, the discrepancies in transition sequence between the experimental and theoretical works was explained by Tsuppayakornaek et al [10]. Regarding transition sequence in Sr., it was investigated by the hybrid exchange-correlation functional, i.e.…”

“…High pressure physics is important for structural phase transitions in materials [8][9][10][11][12][13][14][15][16][17][18]. Regarding a crystal structure of materials under high pressure, it can enhance electronic properties of materials [19][20][21].…”