The planar configuration of the [10¯1] super-dislocation in stoichiometric material was determined, on the basis of the generalized Peierls-Nabarro model, by using γ-surface energies which had been calculated by means of  ab initio  electron theory. The displacement field was parametrized by superposing 4 partial Peierls dislocations. It was deduced, from the calculated separations of partials, that a weak-beam image of the [10¯1] super-dislocation should reveal a superlattice intrinsic stacking-fault ribbon, whereas the complex stacking-fault (antiphase-boundary) ribbon was at or beyond the limit of resolution.

Planar Dissociation of [10¯1] Super-Dislocations in TiAl: Ab Initio Electron Theory and Generalized Peierls-Nabarro Model G.Schoeck, J.Ehmann, M.Fähnle: Philosophical Magazine Letters, 1998, 78[4], 289-95