First-principles calculations of diffusion coefficients: Hydrogen in silicon

Existing calculations of diffusion coefficients in solids have so far relied on empirical potentials and/or dynamical simulations, both of which entail important limitations. We present a practical approach that is based on rate theory and allows the calculation of temperature-dependent diffusion coefficients from static first-principles calculations. Results for hydrogen in silicon are in excellent agreement with recent first-principles dynamical calculations at high temperatures and with experiment. They further elucidate the nature of diffusion pathways and anharmonic effects. © 1990 The American Physical Society.