The Hansen method for the description of adsorption at a curved interface between immiscible liquids: An extension of the Gibbs method

A thermodynamic theory that describes capillary phenomena at an arbitrary curved interface between immiscible liquids is developed. The Gibbs and Hansen methods are interpreted from a geometric point of view. Relations are derived for surface excesses of substance, entropy, and volume for binary liquid systems with a curved interface. As an example, the relations are analyzed for the simplest two-component system αβ when phase α is spherical and lies entirely inside phase β. The Hansen approach, which is an extension of the Gibbs method, gives a deeper insight into the nature of interfacial phenomena and offers a convenient apparatus for describing these phenomena.