First-principles study of Co3(Al,W) alloys using special quasi-random structures

We have developed 32-atom special quasi-random structures (SQSs) to model the substitutionally random pseudo-binary A3(B0.5C0.5) alloys in L12, D019, and D03 crystal structures, respectively. First-principles SQS calculations are performed to examine the phase stability of the recently identified L12–Co3Al0.5W0.5 compound in the Co–Al–W ternary system. By computing total energy as a function of applied strain, the single-crystal elastic constants of L12–Co3Al0.5W0.5 are also predicted and our results show excellent agreement with recent experimental measurements.