Theoretical prediction on the hydrolysis rate of the new types of nerve agents: A density functional study

Md Al Mamunur Rashid; Byounghwak Lee; Kwang Ho Kim; Keunhong Jeong

doi:10.1016/j.toxrep.2022.12.001

Theoretical prediction on the hydrolysis rate of the new types of nerve agents: A density functional study

Toxicol Rep. 2022 Dec 9:10:27-31. doi: 10.1016/j.toxrep.2022.12.001. eCollection 2023.

Authors

Md Al Mamunur Rashid¹, Byounghwak Lee², Kwang Ho Kim¹, Keunhong Jeong²

Affiliations

¹ Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 02792, South Korea.
² Department of Physics and Chemistry, Korea Military Academy, Seoul 01805, South Korea.

Abstract

Although the hydrolysis mechanism of the nerve agents, which is the main decontamination pathway, has been studied experimentally and theoretically, the reliable theoretical prediction method for the hydrolysis rate is not studied yet. Furthermore, after the CWC (Chemical Warfare Agent) list is updated, Novichok candidate structures can be more than 10,000 structures, for which it is not possible to perform the experiment for all of them for synthesizing and getting the hydrolysis rate. Therefore, developing a reliable theoretical method for hydrolysis rate prediction is crucial to prepare for the forthcoming usage of new types of nerve agents. Herein, by using DFT (Density Functional Theory), we successfully developed a new method of predicting the hydrolysis rate on nerve agents by investigating the electrophilicity index (EI) of the various A-, V-, and G-series nerve agents and found a suitable correlation with the experimental hydrolysis rate. Among the several DFT methods, wb97xD predicts the EI with the lowest % deviation of the studied nerve agents. Our results show that EI can be a good indicator to predict the hydrolysis rate of the anticipated nerve agents. Based on the result, we predicted the hydrolysis rate on another type of Novichok candidates, which could be the firm basis for developing a decontaminant and antidote with much fewer experimental efforts on new types of nerve agents.

Keywords: DFT; Electrophilicity; Hydrolysis rate; Nerve agent.