Automated Variable Electric-Field DFT Application for Evaluation of Optimally Oriented Electric Fields on Chemical Reactivity

Recent theoretical work and experiments at molecular junctions have provided a strong conceptualization for the effects of oriented electric fields (OEFs) on organic reactions. Depending on the axis of application, OEFs can increase (or decrease) the reaction rate or distinguish between isomeric pathways. Despite the conceptual elegance of OEFs, which may be applied externally or induced locally, as tools for catalyzing organic reactions, implementation in synthetically relevant systems has been hampered by inefficiencies in evaluating reaction sensitivity to field effects. Herein, we describe the development of the Automated Variable Electric-Field DFT Application (A.V.E.D.A.) for streamlined evaluation of a reaction’s susceptibility to OEFs. This open-source software was designed to be accessible for nonexpert users of computational and programming tools. Following initiation by a single command (and with no subsequent intervention) the Linux workflow manages a series of density functional theory calculations and mathematical manipulations to optimize local-minimum and transition-state structures in oriented electric fields of increasing magnitude. The resulting molecular and reaction dipole moments, field-perturbed geometries, and net effective activation energies are compiled for user interpretation. Ten representative pericyclic reactions that showcase the development and evaluation of A.V.E.D.A. are described.

近期针对分子结的理论研究与实验，为定向电场（oriented electric fields, OEFs）调控有机反应的效应提供了严谨的概念性框架。根据电场施加轴的不同，定向电场可提升（或降低）反应速率，亦可区分异构反应路径。尽管定向电场既可外施亦可局部诱导，作为催化有机反应的工具具备概念上的优越性，但其在合成化学相关体系中的应用仍因难以高效评估反应对电场效应的敏感性而受阻。本文介绍了自动可变电场密度泛函理论应用程序（Automated Variable Electric-Field DFT Application, A.V.E.D.A.）的开发，该工具可简化反应对定向电场敏感性的评估流程。这款开源软件专为计算与编程工具的非专业用户设计，仅需单条命令启动且无需后续人工干预，其搭载的Linux工作流即可自动执行一系列密度泛函理论计算与数学运算，在强度递增的定向电场中优化局域极小值与过渡态结构。最终将整理得到分子与反应偶极矩、电场扰动后的几何结构，以及净有效活化能，供用户解读分析。本文还选取十个典型周环反应案例，用于展示A.V.E.D.A.的开发与验证流程。