Phase Transformations In Beryllium Chalcogenides At High Pressure: Lattice Dynamical Studies

摘要

A transferable shell model potential has been employed to study the pressure-induced solid-solid phase transitions exhibited by BeSe and BeTe. A detailed investigation of the Gibbs free energy has revealed the relative stability of the different phases for BeSe and BeTe. In addition, a microscopic analysis of the polarization of phonons of different energies for the various phases indicate the role played by the tranverse acoustic phonons in the first order phase transition exhibited by these compounds.