Department of Physics, Trento University, Via Sommarive 14, Povo (Trento) I-38100, Italy.
J Chem Phys. 2010 Mar 21;132(11):111102. doi: 10.1063/1.3355866.
We introduce a framework to investigate ab initio the dynamics of rare thermally activated reactions, which cannot be studied using the existing techniques. The electronic degrees of freedom are described at the quantum-mechanical level in the Born-Oppenheimer approximation, while the nuclear degrees of freedom are coupled to a thermal bath, through a classical Langevin equation. This method is based on the path integral representation for the stochastic dynamics and yields the time evolution of both nuclear and electronic degrees of freedom, along the most probable reaction pathways, without spending computational time to explore metastable states. As a first illustrative application, we characterize the dominant pathway in the cyclobutene-->butadiene reaction, using the semiempirical Parametrized Model 3 (PM3) approach.
我们引入了一个框架，用于从理论上研究无法通过现有技术进行研究的罕见热激活反应的动力学。在 Born-Oppenheimer 近似下，电子自由度以量子力学水平描述，而核自由度通过经典 Langevin 方程与热浴耦合。该方法基于随机动力学的路径积分表示，沿着最可能的反应途径得出核和电子自由度的时间演化，而无需花费计算时间来探索亚稳状态。作为第一个说明性应用，我们使用半经验 Parametrized Model 3 (PM3) 方法来描述环丁烯-->丁二烯反应的主要途径。
