Phase behavior of amphiphile-water binary mixtures

In a three-dimensional lattice, another term of the energy is adjusted on t he Shnidman-Zia model in order to obtain the lamellar phase. Phase behavior s of the new Hamiltonian are determined using the perturbation theory and t he mean-field analysis. We investigate the phase diagrams in (T,delta) and (T,rho(a)) planes. The phase diagrams exhibit a rich variety of behavior: s econd-order, first-order, and multicritical points. We find that the lamell ar phase appears for certain values of the parameters of the system. Moreov er, other new phases are obtained that correspond to physical micellar phas es.