Lattice statistics and dynamics within cluster variation method

The conventional Cluster Variation Method (CVM) does not explicitly consider both lattice vibration and local lattice relaxation effects. As discussed in the previous studies, these deficiencies result in overestimation of order-disorder transformation temperatures for the Cu-Au phase diagram. In the present paper, we propose modified CVM which explicitly takes both the effects mentioned above into account. By employing the present modified CVM, we evaluated both lattice vibration and local lattice relaxation effects, and estimated free energy of mixing for Cu-Au disordered phase at a finite temperature.