论文标题
以OH + CH_4的示例计算双分子速率系数的新的稳定和快速的环聚合物分子动力学
New Stable and Fast Ring-Polymer Molecular Dynamics for Calculating Bimolecular Rate Coefficients with Example of OH + CH_4
论文作者
论文摘要
化学反应的速率系数的准确计算是化学动力学研究中的关键问题。在这项工作中，通过在200 K至1500 k的温度范围内应用无尺寸的超稳定的Cayley传播器，在200 k至1500 K的温度范围内，使用RIND POLYMER分子动力学（RPMD）研究了原型高尺寸化学反应OH + CH4-> H2O + CH3的热速率系数。还研究了标题反应的三种同位素学的动力学同位素效应（KIE）。结果表明，即使在深度隧道区域，与实验数据也有很大的一致性。尤其是，Cayley传播器显示出高计算效率，而准确性损失很小。目前的结果证实了RPMD方法的适用性，尤其是Cayley繁殖器的速度，在双分子反应速率的理论计算中。
The accurate and efficient calculation of the rate coefficients of chemical reactions is a key issue in the research of chemical dynamics. In this work, by applying the dimension-free ultra-stable Cayley propagator, the thermal rate coefficients of a prototypic high dimensional chemical reaction OH + CH4 -> H2O + CH3 in the temperature range of 200 K to 1500 K are investigated with ring polymer molecular dynamics (RPMD), on a highly accurate full-dimensional potential energy surface. Kinetic isotope effects (KIEs) for three isotopologues of the title reaction are also studied. The results demonstrate excellent agreement with experimental data, even in the deep tunneling region. Especially, the Cayley propagator shows high calculation efficiency with little loss of accuracy. The present results confirmed the applicability of the RPMD method, particularly the speed-up by Cayley propagator, in theoretical calculations of bimolecular reaction rates.
