Monte Carlo atomistic simulations of the properties of
Σ3⟨111⟩ grain boundaries in W are carried out.
We demonstrate the influence of boron additive on the resistance of
the grain boundary with respect to different shifts. The
interatomic potentials used in these simulations are obtained from
ab initio total-energy calculations. These calculations are
performed in the framework of density functional theory in the
coherent potential approximation. A recursion procedure for
extracting A-B-type interatomic potentials is suggested.