Research Center for Natural Sciences, Hungarian Academy of Sciences , Magyar Tudosok Korutja 2, H-1117 Budapest, Hungary.
Chemistry Research Laboratory, University of Oxford , Mansfield Road, Oxford OX1 3TA, U.K.
J Chem Theory Comput. 2016 Apr 12;12(4):1833-44. doi: 10.1021/acs.jctc.5b01237. Epub 2016 Mar 24.
Transition state force fields (TSFF) treated the TS structure as an artificial minimum on the potential energy surface in the past decades. The necessary parameters were developed either manually or by the Quantum-to-molecular mechanics method (Q2MM). In contrast with these approaches, here we propose to model the TS structures as genuine saddle points at the molecular mechanics level. Different methods were tested on small model systems of general chemical reactions such as protonation, nucleophilic attack, and substitution, and the new procedure led to more accurate models than the Q2MM-type parametrization. To demonstrate the practicality of our approach, transferrable parameters have been developed for Mo-catalyzed olefin metathesis using quantum mechanical properties as reference data. Based on the proposed strategy, any force field can be extended with true transition state force field (TTSFF) parameters, and they can be readily applied in several molecular mechanics programs as well.
在过去几十年中，过渡态力场 (TSFF) 将过渡态结构视为势能表面上的人为最低点。必要的参数要么是手动开发的，要么是通过量子到分子力学方法 (Q2MM) 开发的。与这些方法不同，我们在这里提议在分子力学水平上将 TS 结构建模为真正的鞍点。不同的方法在质子化、亲核攻击和取代等一般化学反应的小模型系统上进行了测试，新方法得到的模型比 Q2MM 型参数化更准确。为了展示我们方法的实用性，我们使用量子力学性质作为参考数据，为钼催化的烯烃复分解开发了可转移的参数。基于所提出的策略，可以使用真正的过渡态力场 (TTSFF) 参数扩展任何力场，并且可以在几个分子力学程序中轻松应用它们。
