Free energy of the concerted-exchange mechanism for self-diffusion in silicon

Abstract

The free energy of the concerted exchange mechanism for self-diffusion in silicon is estimated using the thermodynamic integration method and Monte Carlo (MC) simulations with an interatomic potential fitted to reproduce local-density-approximation calculations. Anharmonicity and relaxation are fully taken into account in the calculations, since the phase space is extensively explored by the MC simulations. The results indicate that the concerted exchange mechanism can have a significant contribution to the self-diffusion constant in silicon. © 1996 The American Physical Society.