Thermodynamic approach to segregation at the interface of two condensed phases

Nowadays, the thermodynamic theory of interface segregation does not rest on a solid base. Lack of experimental data is the source of the difficulties encountered in the validation of the theoretical models. In this work, we present a simple thermodynamic theory for the calculation of some physico-chemical properties of the interface between two condensed phases α and β, namely chemical composition, interface tension, adhesion and wetting. It has been shown that in the case of an ideal system, the thermodynamic properties of the constituents in the pure states are sufficient for the estimation of the interface thermodynamic properties. In real systems, knowledge of the phases miscibility energies is indispensable. In the frame of the proposed thermodynamic theory, surface segregation appears only as a particular case.