Development of Reaction Density Functional Theory and Its Application to Glycine Tautomerization Reaction in Aqueous Solution
2018
Tang, Weiqiang | Cai, Cheng | Zhao, Shuangliang | Liu, Honglai
Accurate determination of reaction barrier is crucial in chemical reaction engineering since it is directly associated with the reaction rate and reaction path. Whereas massive quantum calculations relying on commercial software have been reported for understanding reaction mechanisms, the solvent effect on the reaction barrier is still poorly understood. The difficulty originates partially from the ill capture of the inhomogeneous solvent structure around the reaction site. Herein, we propose a reaction density functional theory (RxDFT) by combining the quantum density functional theory for calculating intrinsic reaction energy with the classical density functional theory for addressing solvation contribution. For demonstration, the glycine tautomerization reaction in aqueous solution is revisited by using RxDFT. We illustrate that the free energy profiles of two distinct reaction paths can be well predicted, in comparison with the results of molecular dynamics/MP2 simulation. Since no solvent molecule is explicitly considered, the developed RxDFT is promising to provide an efficient alternative to the quantum mechanics/molecular mechanics approach or ab initio calculation.
显示更多 [+] 显示较少 [-]