Xue, Bai2019-02-122019-02-122018-09https://hdl.handle.net/11299/201682University of Minnesota Ph.D. dissertation.September 2018. Major: Chemistry. Advisor: Ilja Siepmann. 1 computer file (PDF); vi, 174 pages.Microheterogenous systems play an essential role in many aspects of chemistry. For example, understanding the bubble or droplet nucleation processes enable us to investigate atmospheric chemistry such as rain and cloud formation. The interfacial eects often involve enrichment, thus can be used in adsorption and separation. Decreasing interfacial tension has the application of surfactant. The heterogeous solvation environment studies may lead us to understand the most important process in life such as protein folding and membrane formation. Because of their fundamental importance, many methods of both experiment and theory are developed to understand their mechanism. However, experiments are very dicult to conduct in very extreme conditions, for example, the high temperature and high pressure condition in the oil reservoir and complicated environment in atmosphere. On the other hand, most of the theoretical methods still need empiricism thus are dicult to provide physical insight. Hence, molecular level simulations provide a promising alternative approach to study complex heterogenous systems. The Monte Carlo and molecular dynamics simulations have been employed in this thesis to study many important applications including bubble nucleation, water/alkane phase equilibria, micro-solvation environment of a chromophore, and interfacial tension of water/ oil. Results show that these simulations can yield accurate prediction of macroscopic properties meanwhile reveal molecular level structure, which demonstrate that molecular simulations are indeed powerful new tools to study complex heterogeneous systems.enabsorption spectrabubbly waterinterfacial tensionMonte Carlowater/alkane mutual solubilityThesis or Dissertation