Density-functional studies of amphiphilic binary mixtures. II. Gas-liquid nucleation

Density-functional theory is applied to study gas-liquid nucleation in bina ry mixtures consisting of Lennard-Jones atoms with hard-spherical cores (mo nomers) and bonded Lennard-Jones atoms of two (dimers) or three (trimers) h ard spheres. Mixtures with and without amphiphiles are compared. In amphiph ilic systems mutual enhancement of nucleation is observed regardless of red uced total interaction between the molecules. Monomer-dimer and monomer-tri mer mixtures are compared. Increased chain length is shown to result in str onger enhancement of nucleation. Layered structures are shown to form in la rge critical clusters at certain vapor activities. The nucleation behavior of the amphiphilic systems resembles qualitatively the experimental observa tions of water-n-alcohol mixtures. (C) 2000 American Institute of Physics. [S0021-9606(00)51134-9].