A molecular theory of interfacial phenomena in multicomponent systems

摘要: The van der Waals theory of surface tensions is generalized to multicomponent systems. local free energy density consists a ’’local equilibrium’’ (i.e., equilibrium uniform mixture having species densities equal the densities) plus quadratic form in gradients densities. coefficients this depend on through dependence second moment direct correlation function. requirement that be minimum yields system partial differential equations (one for each component). A particular linear combination condition mechanical equilibrium. It can interpreted as microscopic statement Young–Laplace equation pressure variation across curved interface. For two component systems generalization treatment Cahn and Hilliard it allows variations. If fluctuations are suppressed, concentration very similar theirs, except total may vary Similarly, when applied liquid–vapor binary system, number reduces single chemical potential difference (μ=μ1−μ2) held constant.