Dg. Pettifor et al., DEFECT MODELING - THE NEED FOR ANGULARLY DEPENDENT POTENTIALS, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 193, 1995, pp. 24-30
The reliable atomistic simulation of defects in intermetallics require
s the development of angularly dependent interatomic potentials. Ab in
itio calculations predict, for example, that the nearest competing pha
ses to the L1(0) ground state of TiAl and the B2 ground state of NiAl
are B33 (CrB) and B20 (FeSi) respectively, whose structural stability
is determined by directional pd bonding. This is well described by the
Tight Binding model, within which approximation angularly dependent m
any-atom interatomic potentials have recently been derived. The nature
of these so-called Bond Order Potentials (BOPs) and their application
to structural prediction in elemental d-valent transition metals and
sp-valent semiconductors are discussed.