Investigating single and multicomponent phase coexistence and nucleation properties for some simple models: From charged hard dumbbells to Lennard-Jones mixtures

CHED 989

Michael DeLee, Lawrence J. Tauzin, Samuel J. Keasler, skeasl1@lsu.edu, Ricky B. Nellas, rnella1@lsu.edu, and Bin Chen, binchen@lsu.edu. Department of Chemistry, Louisiana State University, 400 Choppin Hall, Baton Rouge, LA 70803
Despite extensive experimental and theoretical research into phase behavior and nucleation, there remain a number of significant unanswered questions, even for simple systems. Multi-component systems of particles of different sizes have been shown to exhibit interesting phase and nucleation behavior. How the size difference affects these properties can be of interest in colloidal and polymeric chemistry. Similarly, the existence of a stable liquid phase for the dipolar hard sphere system has long been in dispute. Attempts to probe this system directly have been complicated by its strong aggregation. Charged hard dumbbells, which are equivalent to dipolar hard spheres in the limit of zero bond length, have been used to model this system. However, for very short bond lengths, these systems remain difficult to examine. We have studied the phase behavior and nucleation of the charged hard dumbbell system and of binary and ternary mixtures of Lennard-Jones particles of different sizes. This work highlights the advantages of the AVBMC Gibbs ensemble approach and the AVUS-HR algorithm for probing this type of behavior.