Specific volume and entropy of formation of the interface of two immiscible liquids

A rigorous thermodynamic determination of the specific characteristics of formation of the phase boundary: volume, entropy, and energy, is given. They were calculated with the Hansen method. The specific characteristics of the formation of the phase boundary coincide with the coefficients in the Gibbs adsorption equation in the Hansen representation only in the simplest case of a two-component, two-phase system. In the general case, a system of equations for determining the values sought is obtained. Its solution was found for a series of the most important special cases, for example, for a three-component, two-phase system. A comparison with other concepts of the characteristics of the formation of an interface available in the literature was conducted, and the limitations of these concepts were indicated.