First-principles computation of the vibrational entropy of ordered and disordered Ni₃Al

Abstract

There is increasing evidence that vibrational entropy may significantly contribute to the entropy difference between the ordered and the disordered states of a compound. Through first-principles calculations, we investigate the magnitude of this vibrational entropy difference in Ni₃Al, a compound where this effect is believed to be especially large. We find the vibrational entropy difference to be essentially zero and temperature independent.