Analysis of structural phase stability and thermo-elastic properties of alloy of rare earth sulfides (LaxPr1-xS) under high pressure at room temperature

Abstract

The high pressure structural behavior and associated properties of mixed rare earth sulfides (LaxPr1-xS) have been investigated by applying a Realistic Interaction Potential (RIP) model, including temperature effects. This model explains the inter-atomic interactions as it incorporates long range coulomb interaction; three body interaction (TBI), vdW (van der Waals) interaction, short range overlap repulsive interaction up to second neighbors and zero point energy effects including the temperature effects. We have predicted the high pressure structural phase transition from NaCl (B1 -type) to CsCl-type (B2-type) phase and associated volume drops for these compounds. The pressure induced phase transition is found to be a first order. Estimation of the elastic, thermal properties and Every’s parameters of these compounds has been performed during study. The results obtained are found to be in reasonable agreement with experimental and other theoretical data.