Correlating interfacial tensions with surface tensions: a gibbsian approach.

The Gibbs approach to the definition of interfacial and surface tensions is used for developing a general form for a correlation between interfacial tensions and their corresponding surface tensions. This general equation can serve as a starting point for either further fundamental development or an empirical search for a correlation that fits experimental data. In this Article, the latter approach is followed. The general equation is transformed by a few reasonable assumptions into a relatively simple framework for empirically correlating interfacial tensions with their corresponding surface tensions. The agreement of results of the present empirical correlation with a large body of experimental data for interfacial tensions in saturated liquid-liquid systems is better than that of previously suggested correlations. It is hoped that this correlation will be useful also for solid-liquid interfacial tensions, for which direct measurements are not yet available.