Developing Quantum Mechanically-Based Force Field Parameters from Gas Hydrates to Biology

Prof. Stanley Sandler was one of the pioneers in the chemical engineering field to utilize quantum mechanical (QM) methods for applications to phase equilibria via thermodynamic models and developing force field parameters for use in molecular simulations. I was fortunate to work under Prof. Sandler during this time period as a Ph.D. student in developing guest-host interaction potentials in gas hydrates. In this talk, I will summarize how QM was used to develop accurate guest-water potentials for use in predicting gas hydrate phase equilibria and guest adsorption in its water lattice. This fundamental approach to force field development was extended to a more complex class of biomolecules, i.e., lipids. QM methods are currently used in predicting torsional energy profiles that are then fit to potential functions in complex biomolecular force fields. Moreover, QM has been used to guide fits for the partial charge distribution and other non-bonded interactions in lipid force fields. The high accuracy of the CHARMM36 pairwise additive lipid force field will be presented and a prospective on future lipid force field development needs will also be be included.