William Noid of the Pennsylvania State University is supported by an award from the Chemical Theory, Models and Computational Methods Program in the Chemistry Division to develop theoretical methods and computational tools for simulating the thermodynamic and interfacial properties of liquids and polymers. Computer simulations provide powerful insight for addressing technological challenges and for guiding the design of novel materials with desired properties. While simulations with atomically detailed models are often very accurate, they do not provide the necessary efficiency for addressing the long length and time scales that are relevant for materials design. In contrast, lower resolution coarse-grained models provide superior efficiency, but currently provide limited accuracy and often require extensive parameterization for each new system and environment. Professor Noid and his coworkers develop theoretical methods for improving the accuracy of coarse-grained models, as well as for extending their range of applicability. Additionally, Professor Noid organizes an intergenerational science club that promotes life-long scientific education within the broader community, while integrating students of all ages into the scientific enterprise.
This project develops and validates a van der Waals (vdW) approach for improving both the transferability and also the thermodynamic properties of bottom-up multiscale methods. Motivated by an exact decomposition of the many-body potential of mean force, which is the correct potential for a coarse-grained (CG) model. This model perfectly reproduces both the structural and thermodynamic properties of an underlying atomistic model. The vdW approach: (1) adopts leading variational methods to determine effective potentials that accurately describe structural properties and (2) develops new variational methods to accurately model thermodynamic properties. In particular, the work extends a pressure-matching variational principle for modeling density fluctuations in inhomogeneous and interfacial systems. The comparison of potentials obtained from different variational approaches provides insight into their entropic components and allow for predictive estimates of their transferability. Ultimately, this work may develop predictive CG models for exceedingly accurate and efficient simulation studies of mesoscale self-assembly at aqueous interfaces and conduction in polymer-based batteries.
|Effective start/end date
|4/1/16 → 3/31/20
- National Science Foundation: $420,000.00