1. Understanding the nucleation mechanism of the ternary
water / n-nonane / 1-butanol system
Bin Chen
Department of Chemistry, Louisiana State University
How does the vapor-liquid nucleation of water / n-nonane / 1-butanol proceed?
With the use of AVUS-HR approach, which combines aggregation-volume-bias Monte Carlo (AVBMC) and self-adaptive umbrella sampling (US) with histogram reweighting (HR), we performed atomistic simulations on a ternary water/n-nonane/1-butanol system. A close examination of the obtained nucleation free energy landscape reveals various sets of paths at different vapor-
phase compositions. For instance, at low n-nonane activities, nucleation proceeds via a single binary-like water (W) / 1-butanol (B) channel (see Figure A). While at intermediate n-nonane activities, nucleation goes through various channels (see Figure B) such as binary-like water (W) / 1-butanol (B) and binary-like n-nonane (N) / 1-butanol (B) mixing behaviors. This mechanistic variety is the microscopic origin for the complex nucleation behavior observed for this ternary mixture.
(A)
(B)