It was recalled that, although B2-NiAl had one of the simplest crystal structures of any intermetallic compound, its atomic transport mechanisms were complex and poorly understood. A first-principles study was made here, of diffusion in B2-NiAl, that simultaneously accounted for all relevant hopping mechanisms in kinetic Monte Carlo simulations. Diffusion in B2-NiAl occurred not only through first- and second-nearest-neighbor hops, but also through simultaneous pair-atom hops with the dominant transport mechanism being very sensitive to the bulk alloy concentration and degree of local disorder.

Atomic Transport in Ordered Compounds Mediated by Local Disorder: Diffusion in B2-NixAl1-x. Q.Xu, A.Van Der Ven: Physical Review B, 2010, 81[6], 064303