Scholar: Alberto Nava
Major: Chemical Engineering & Applied Math
Faculty Mentors: Dr. Victor Vazquez
Research Topic: Stability of Reverse Micellar Systems with Salt Additions: Insights from Molecular Dynamics
Abstract: A micelle is an aggregate structure formed by the sequestration of a non-polar solvent, by the hydrophobic tails that are characteristic of amphiphilic surfactants, from an aqueous solution. Conversely, reverse micelles (RM) are aggregate structures formed by the sequestration of aqueous solutions from a surrounding non-polar solvent. Reverse micelles, in particular those formed by the AOT/water/isooctane system, are commonly used as nanoreactors for nanoparticle synthesis. Due to the high dependence that nanoparticles have on their size, the morphology of reverse micelles under various conditions is of significant interest. Particularly, experiments show that salt additions, such as zirconium (Zr), within the aqueous core of the reverse micelle reduces the average size of the structures. The fundamental mechanisms underlying this transition are not clear from both experimental and modeling perspectives. This work seeks to elucidate such mechanisms using atomistic modeling within a molecular dynamics framework using fully atomistic force fields for the water core and surfactant and coarse-grained force fields for the solvent. We will use the GROMACS platform to integrate Newton's equations of motion with well-known force fields such as Charmm27 and with an in-house optimized force field for the solvent. Preliminary simulations show that the potential formation of heteronuclear structures might play a significant role in the stability of RMs. We plan to further test and
validate this hypothesis by modeling these systems with salt additions using additional long-range interactions for the added high charge cations. Preliminary results of our simulations will be presented.
New Scholar: 2017 cohort