Structural, vibrational and thermodynamic properties of Zirconium–cobalt: First-principles study

To evaluate ZrCo as a getter material for the storage of hydrogen and its isotopes, the structural, vibrational and thermodynamic properties of ZrCo are investigated by first-principles. The calculated phonon frequencies at the Γ point are assigned using density-functional perturbation theory (DFPT). The phonon dispersion curves along several high-symmetry lines at the Brillouin zone and the phonon density of states are also calculated. The thermodynamics properties including the phonon contribution to the Helmholtz free energy ΔF, the internal energy ΔE, the entropy S, and the constant-volume specific heat Cv are determined within the harmonic approximation based on the calculated phonon density of states.