** We used the Voter-Chen EAM-potential to obtain a relaxed configuration of the edge dislocation with b=aO on (001) glide plane. Periodic boundary conditions (BCs) have been imposed in the z-direction (coinciding with the dislocation line) with different types of BCs considered in the x- and y-directions. This slip system, dominant for B2 NiAI, was not observed experimentally in Ni3AI. However, as can be seen from Fig. 1, a stable dislocation core with easily recognizable structure was forrned in our simulations, and it can be considered as a good example of the Peierls model of a dislocation, .
*** We do not consider in this work a numerical approach described in detail by Kubin which is connected with the direct evaluation of forces acting between dislocations using the Peach-Koehler equationl .