20-09E

A model of competing pair interaction in the form of a three-Yukawa (3Y) potential is considered. The results of computer simulations show that the model proposed can describe spontaneous appearance in a homogeneous fluid of a large variety of mesostructured phases. Furthermore, these self-assembly effects appear to be favored by the presence of confining walls. To study the structure and thermodynamics of a mesoscopically homogeneous 3Y fluid in the bulk and close to a hard wall, a field theory approach is subsequently applied. Explicit analytical expressions for the pair correlation function and the density profile are derived. The structure factor is calculated by introducing an effective hard core radius characteristic of the system, based on which the λ-lines are constructed and phase behavior discussed.