Ab-initio calculation of the pressure dependence of phonons and elastic constants for Al and Li

Abstract

We calculated the interionic potentials for aluminium and lithium from first principle pseudopotentials. We constructed these pseudopotentials from the induced electron densities around an aluminium nucleus and around a lithium nucleus respectively. Then we calculated the phonon dispersion curves and the elastic constants. We repeated the whole calculation for several values of pressure by changing, each time, the value of the electron gas density parameter rs. The induced electron densities were calculated using Density Functional Theory.