Linear Scaling DFT for defects in metals

摘要

This work presents a study of defects in solids using Density Functional Theory (DFT) as the only input to predict its formation energies. The method used, called the Linear Scaling Spectral Gauss Quadrature (LSSGQ), has linear scaling with the number of atoms for insulators as well as for metals. This behaviour allows us to simulate relatively large systems in a fraction of the time demanded by other traditional DFT methods. We demonstrate the effectiveness of the method, the linear scaling of large problems and also the size dependence in the formation energy of defects through the simulation of (001) surface relaxation and single vacancy in Body Centered Cubic (BCC) Sodium crystals.