(590f) Reaction Density Functional Theory and Its Application to SN2 and Nucleophilic Addition Reactions in Aqueous Solution

Solvents have profound effects on activation free energy and reaction free energy in chemical reactions, which are directly associated with the reaction rate and reaction path. Hence, efficient and accurate methods for predicting solvation effects are vitally important in chemical reaction engineering. Herein, we propose a multiscale reaction density functional theory (RxDFT) by combining the quantum density functional theory (QDFT) for calculating intrinsic reaction energy, and with the classical density functional theory (CDFT) for dealing with solvation effects. In this work, the hybrid method is applied to study the solvation effects on S_N2 reactions and nucleophilic addition reactions, which are both the typical and fundamental reactions in organic chemical reaction. The total free energy profiles along the reaction coordinate for those reactions agree well with the results from previous calculations. In conclusion , RxDFT can accurately predict the activation free energy and reaction free energy in several chemical reactions in aqueous solvent, and it can be extended to deal with inhomogeneous reactions subject to different solvent environments.