Simulation of interstitial diffusion in graphite

First-principles method based on the density-functional theory is used to study the diffusion of the single carbon interstitial in graphite. Possible diffusion processes in directions both parallel and perpendicular to the basal plane are analyzed. A different path for the interstitial to penetrate the graphitic layer is proposed. Along this path, the migration is carried out through atom exchange between the interstitial and the lattice atom, with a barrier lower than 0.5 eV. Introducing shear into the graphite may reduce the interstitial migration energy.