MICROSCOPIC MODEL FOR MIXED SURFACTANT VESICLES

A microscopic model which has proven useful in describing amphiphilic aggregates as inhomogeneities of a fluid is extended here to study the case of a two-component surfactant mixture. We have chosen an effecti ve interaction between the amphiphiles that mimics the mixture of cati onic-anionic surfactants. In agreement with experiments, and other the oretical approaches, we find regions where spherical vesicles are stab le, with a well-defined radius. The experimental dependence of the rad ius on the chemical environment is also qualitatively reflected in our model.