Gaussian, Inc., 340 Quinnipiac Street, Building 40, Wallingford, Connecticut 06492, USA.
J Chem Phys. 2010 Dec 14;133(22):224101. doi: 10.1063/1.3514202.
The theoretical treatment of chemical reactions inevitably includes the integration of reaction pathways. After reactant, transition structure, and product stationary points on the potential energy surface are located, steepest descent reaction path following provides a means for verifying reaction mechanisms. Accurately integrated paths are also needed when evaluating reaction rates using variational transition state theory or reaction path Hamiltonian models. In this work an Euler-based predictor-corrector integrator is presented and tested using one analytic model surface and five chemical reactions. The use of Hessian updating, as a means for reducing the overall computational cost of the reaction path calculation, is also discussed.
化学反应的理论处理不可避免地包括反应途径的积分。在确定了势能面上的反应物、过渡态结构和产物稳定点之后，最陡下降反应路径追踪为验证反应机理提供了一种手段。在使用变分过渡态理论或反应路径哈密顿模型评估反应速率时，也需要准确积分的路径。在这项工作中，提出并测试了一种基于欧拉法的预测-校正积分器，使用了一个解析模型表面和五个化学反应。还讨论了使用 Hessian 更新来降低反应路径计算的总体计算成本的方法。
