DFT calculations were used to determine the activation energies (Ea values) for the diffusion of defects such as O atoms (Oi0 red sphere in the picture) in silicon (blue spheres). The migration paths were obtained from the nudged elastic band method. The activation energies calculated with four exchange-correlation functionals (Exc) were compared to experimental data. The Ea values of “atomic-like” interstitials were mostly independent of Exc, but those of strongly bound impurities were sensitive to the choice of Exc.

Activation Energies for Diffusion of Defects in Silicon: the Role of the Exchange-Correlation Functional. S.K.Estreicher, D.J.Backlund, C.Carbogno, M.Scheffler: Angewandte Chemie, 2011, 50[43], 10221-5