On the microscopic theory of quantum binary solutions

A quantum binary solution of hard spheres is investigated by the method of functional integration. The thermodynamic potential of the system is calculated up to terms quadratic in the diameters of the spheres. Also obtained are expressions for the matrix elements of the two- and three-particle cluster operators for the hard-sphere model in the momentum representation. The result of calculation of the thermodynamic potential is represented in the form of a virial expansion in powers of the activities.