Impurity-vacancy and vacancy-vacancy binding energies in α-iron

Abstract The impurity-vacancy and the vacancy-vacancy binding energies in α-iron are estimated in a simple electronic model. The band structure of the pure metal is described by a hybridized tight binding nearly free electron (TB-NFE) model adjusted to a self-consistent KKR calculation. Results of the vacancy-vacancy binding energy are compared with previous calculations. It is shown that the impurity-vacancy binding energy is an important part of ΔQ, the difference between the activation energies for impurity diffusion and for self-diffusion. An attempt is made to understand the influence of the magnetic properties upon the binding energies.