The thermodynamic properties of thermal and athermal (111) antiphase boundaries were calculated from first principles. The effect of off-stoichiometry, partial disordering and segregation were evaluated, and a rough estimation of the vibrational contribution to the antiphase boundary energy was made. It was found that, although the vibrational effect was small, the configurational effects were large. Therefore, at non-zero temperatures and in off-stoichiometric material, the antiphase boundary energy could be only half of that in the perfectly ordered stoichiometric material at zero temperature. It was suggested that there was a discrepancy between electronic structure calculations and experimental measurements.

The Effect of Segregation and Partial Order on the Thermodynamics of (111) Antiphase Boundaries in Ni3Al. Sluiter, M., Hashi, Y., Kawazoe, Y.: Computational Materials Science, 1999, 14[1-4], 283-90