【摘要】 寻找表征化学反应的反应坐标通常是一项困难的任务.作者在之前发表的一篇文章[ACS Cent.Sci.3,407 (2017)]中,通过贝叶斯学习算法优化水中(反向)克莱森重排反应的反应坐标,发现成键键长与断键键长的线性组合是所有测试中最好的.本文考虑了过渡态的非线性特性,提出了一种基于等距特征映射和局部线性嵌入的方法来获得由几个集合变量组成的反应坐标.利用这种方法,作者找到了一个更合理的一维反应坐标,从而可以很好地描述反应进程.为了探索反应机理,本文分析了分子内禀性和溶剂和溶质相互作用相关的物理量对所获得的非线性反应坐标的贡献.此外,还发现第二维坐标能够表征反应机制的异质性.更多还原

【Abstract】 Deriving reaction coordinates for the characterization of chemical reactions has long been a demanding task. In our previous work [ACS Cent.Sci. 3, 407(2017)], the reaction coordinate of a(retro-) Claisen rearrangement in aqueous solution optimized through a Bayesian measure,a linear combination of bond lengths formation and breakage, was judged to be optimal among all trails. Here, considering the nonlinearity of the transition state, we use isometric mapping and locally linear embedding to obtain one reaction coordinate which is composed of a few collective variables. With these methods, we find a more reasonable and powerful one-dimensional reaction coordinate, which can well describe the reaction progression. To explore the reaction mechanism, we analyze the contribution of intrinsic molecular properties and the solventsolute interactions to the nonlinear reaction coordinate. Furthermore, another coordinate is identified to characterize the heterogeneity of reaction mechanisms.更多还原