C. Amador et G. Bozzolo, FORMATION ENERGY OF DISORDERED ALLOYS FROM THE ENERGETICS OF ORDERED COMPOUNDS, Physical review. B, Condensed matter, 49(2), 1994, pp. 956-960
The cluster expansion technique is used in combination with first-prin
ciples calculations of the total energy of ordered compounds to study
the energetics of the disordered phase for a number of alloy systems.
The effect of short-range order, as seen in the energy differences bet
ween an alloy with the configuration corresponding to finite temperatu
re and the perfectly random one is studied. The role of relaxation due
to large size mismatch is discussed in terms of an effective cluster
volume approximation. Very good agreement with measured energies of fo
rmation is obtained when short-range order and relaxation effects are
taken into account.