Energetics of surface defects: towards a simplified model

The energetics of some surface defects for the (111), (100) and (110) surfaces of Cu are calculated using a many-body potential. These formation energies allow a lattice-gas model to be defined, which is very useful in performing large-scale Monte Carlo simulations in order to study the morphology of surfaces within realistic energetic models. We show that some defects are very sensitive to the curvature of the site energy as a function of the coordination number, α. In the case of the potential used for Cu in the present study, the site energy is an almost linear function of the coordination number in a wide range of values of α, allowing an easy and accurate determination of the formation energy of surface defects.