Incorporation of surface correction and anharmonic correction to vacancy formation energy for nickel and copper: bridging the gap between Density Functional Theory and experiment

摘要: Density functional theory (DFT) has been used to estimate vacancy formation enthalpy (H_fv) for a few transition metals like nickel (Ni) and copper (Cu). It is shown that, these metals, H_fv underestimated considerably by DFT. The aim of the present work bridge gap between estimates made DFT calculations experiments. sources this discrepancy are identified as be related opening up surface region surrounding vacancy, temperature induced anharmonic contribution. correction estimated jellium based model originally proposed Mattsson et al. [Phys. Rev. B 73 (2006) 195123] subsequently modified Nandi [J. Phys.:Cond. Matt. 22 (2010) 345501]. In paper, we have contribution using density perturbation theory. Finally, it that incorporation both H_fv, results in better agreement with experimental data.