Pressure-induced structural phase transition and elastic properties in rare earth CeBi and LaBi

A comprehensive first principles study of structural, elastic, electronic and phonon properties of rare-earth CeBi and LaBi is reported within the density functional theory scheme. The ground state properties such as lattice constant, elastic constants, bulk modulus, and finally the phase transition and lattice dynamical properties of rare-earth CeBi and LaBi of rocksalt (B1) and CsCl (B2) structures are determined. The electron band structures for the two phases of both rare-earth crystals are presented. We have calculated phonon dispersion curve, showing that all phonon modes in phonon dispersion curves of B1 phase in CeBi and LaBi are positive, which indicates a stable phase for this structure.