Using eigenvector-following we have calculated minima, transition states and rearrangement mechanisms for face-centred-cubic (fcc) solids bound by a Sutton–Chen (SC) Ni potential. Our results indicate that the divacancy mechanism is the most significant factor in the upward curvature of the Arrhenius plot for the diffusion coefficient. We were unable to identify any true double- or correlated-jump mechanisms in either mono- or divacancy structures. The low migration energies of interstitial defects are balanced by high formation energies which preclude them from contributing significantly to diffusion rates. Calculations based upon cells containing only 100 atoms have been criticised because of the unrealistically high effective defect concentrations when compared with a real solid at the melting point. We compare results for cells containing 256 and 500 atoms and conclude that our calculated stationary points are actually quite well converged.