Antiphase-boundary energies calculations

Using the constructed potentials the y-surface for the (111) plane was calculated. (For more details see Girshick and Vitek 1995). T e lowest energy minimum on this surface corresponds to the ideal Llo structure. However, there are three different metastable stacking fault type defects on (111) the antiphase boundary (APB), the complex stacking fault (CSF) and the superlattice intrinsic stacking fault (SISF). The displacements... 

Simulation methods based on first principles are becoming available, but the number of atoms that is tractable at present is significantly fewer than what dislocation studies require (De Fontaine, 1992 Pettifor, 1992), implying approximations at various levels. As with most techniques, simulations are not in general fully reliable (see antiphase-boundary (APB) energy calculations in NijAl and in NiAl (Chapter 21 by Sun in this volume), and the situation does not improve when dealing with more complicated defects such as dislocation cores. Simulations may nevertheless be helpful in solving problems that would otherwise require intuition. 

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