Energy of mixing and entropy of mixing for Cu$_{x}$Al$_{1-x}$ liquid binary alloys

The free energy of mixing and the entropy of mixing for Cu$_{x}$Al$_{1-x}$ liquid binary alloys have been systematically investigated by using the electronic theory of metals along with the perturbation approach at a thermodynamic state $T=1373$ K. The interionic interaction and a reference liquid are the fundamental components of the theory. The interionic interaction is described by a local pseudopotential. A liquid of hard spheres (HS) of two different effective diametres is used to describe the reference system for alloys. The results of the calculations for energy of mixing agree well with the available experimental data. Calculation of entropy of mixing is parameter free and, the agreement with experiment, in this case, is found to be fairly good.