The predictive power of first-principles calculations of vacancy formation energies in metals was improved by adding a correction for the intrinsic surface error in current implementations of density functional theory. The derived correction was given as a function of electron density, and could be explicitly applied to a wide range of systems. Density functional theory underestimated the vacancy formation energy when structural relaxation was included. This was the case when using either the local density- or the generalized gradient approximation for the exchange-correlation energy. Upon correcting for the intrinsic surface error, excellent agreement was obtained between calculated values using the 2 exchange-correlation functionals. The final value for the vacancy formation energy was 1.16eV. This value was in good agreement with experimental data. The barrier to vacancy diffusion was also calculated to be 1.43eV.

Calculating the Vacancy Formation Energy in Metals - Pt, Pd, and Mo. T.R.Mattsson, A.E.Mattsson: Physical Review B, 2002, 66[21], 214110