The cohesive energies of L12, D022, D023 and selected 1-dimensional long-period structures based on the L12 structure in the Ni-V system for the Ni3V composition were obtained by ab-initio calculations using the Vienna ab initio simulation package. Relaxations, both external and internal with respect to the cell, were taken into account in the determination of the structural stability of the 1-dimensional long-period structures. At each stage of the relaxation process the D022 structure was the ground state. The

values of the (001) antiphase-boundary energies were obtained from the energy differences of 1-dimensional long-period structures with respect to either L12 or D022, with stacking of at least three L12 cubes along the direction perpendicular to the antiphase-boundary. The energy effects in the 1-dimensional long-period structures were described in the framework of an axial next-nearest neighbour Ising model. The values of the interaction parameters were obtained in the ideal, distorted and fully relaxed structures. The antiphase-boundary energies were also derived from these parameters. The results showed that it was necessary to consider long-range interactions in order to obtain reliable values of the antiphase-boundary energies. The results showed also the influence of the relaxation effects on the antiphase-boundary energies.

Ab initio Determination of the (001) Antiphase-Boundary Energy in the D022 Ni3V Compound. C.Colinet, A.Pasturel: Philosophical Magazine B, 2002, 82[16], 1715-29