| Popis: |
The predictive calculations of vacancy formation energies in metals: Cu, Ag, Ni, Pt, Au, Pd, Ir and Rh are presented. The energy is given as a function of electron density. Density functional theory underestimates the vacancy formation energy when structural relaxation is included. The unrelaxed mono-vacancy formation, unrelaxed di-vacancy formation, unrelaxed di-vacancy binding and low index surface energies of the fcc transition metals Cu, Ag, Ni, Pt, Au, Pd, Ir and Rh has been calculated using embedded atom method. The values for the vacancy formation energies agree with the experimental value. We also calculate the elastic constants of the metals and the heat of solution for the binary alloys of the selected metals. The average surface energies calculated by including the crystal angle between planes (hkl) and (111) correspond to the experiment for Cu, Ag, Ni, Pt and Pd. The calculated mono-vacancy formation energies are in reasonable agreement with available experimental values for Cu, Ag, Au and Rh. The values are higher for Pt and Ir while smaller values were recorded for Ni and Pd. The unrelaxed di-vacancy binding energy calculated agrees with available experimental values in the case of Cu, Ni, Pt and Au. |
