Development of an Ionic Liquid Force Field for QM/MM Simulations

点击翻译按钮获取中文摘要

Orlando Acevedo of Auburn University is supported by the Chemical Structure, Dynamics, and Mechanisms program and the NSF EPSCoR office for research to develop a comprehensive set of force field parameters for the simulation of hundreds of widely used ionic liquid combinations and next-generation alternatives with superior biodegradation and lower toxicity. Ionic liquids are a unique class of solvent, generally defined as a material containing only ionic species with a melting point below 100 deg. C. Mixed quantum and molecular mechanics (QM/MM) Monte Carlo calculations featuring the custom force field and free-energy perturbation theory are used to elucidate how ionic liquids operate to enhance rates and/or shift mechanisms for three reaction categories: aromatic nucleophilic substitutions (SNAr), base-induced beta-eliminations, and keto-enol tautomerizations. The research objective is to establish a firm understanding of the intermolecular interactions occurring between ionic liquids and important chemical reaction classes.With over 100 million pounds of chemical waste treated yearly, a better understanding of how to optimize recyclable ionic liquids for chemical reactions has the potential to impact society from the lab bench top to large-scale industrial manufacturing. In addition, this project expands the number of ionic liquid force field parameters available for simulation. The new parameters and equilibrated systems will be made freely available to the scientific community through a website. This proposal introduces computational chemistry to high school and undergraduate students through a hands-on "Instant Supercomputer!¨ workshop featuring the construction of a temporary supercomputer. The project will expose students to cutting edge research and will present an opportunity to do "public science" to solve a research problem with a real time audience, rather than disseminating prior results.