High-pressure lattice dynamics and thermodynamic properties of Th: An ab initio study of phonon dispersion curves

摘要: Phonon dispersion curves and thermodynamics of actinides are hardly accessible for both theory experiments. In this paper we present an ab initio study the properties thorium within framework quasiharmonic approximation by using density-functional pseudopotential method. First compare phonon spectrum obtained at zero pressure with inelastic neutron scattering Thereafter use dispersions to obtain $PVT$ equations state derive thermodynamic quantities from free energy. Then our results thermal volume expansion, bulk modulus, heat capacity, or Debye temperature experimental values when existing. The show a promising agreement experiment propose several predictive behaviors.