Paenurk Eno, Chen Peter
Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland.
J Phys Chem A. 2021 Mar 11;125(9):1927-1940. doi: 10.1021/acs.jpca.1c00183. Epub 2021 Feb 26.
The Rice-Ramsperger-Kassel-Marcus (RRKM) theory provides a simple yet powerful rate theory for calculating microcanonical rate constants. In particular, it has found widespread use in combination with gas-phase kinetic experiments of unimolecular dissociations to extract experimental bond dissociation energies (BDEs). We have previously found several discrepancies between the computed BDE values and the respective experimental ones, obtained with our empirical rate model, named L-CID. To investigate the reliability of our rate model, we conducted a theoretical analysis and comparison of the performance of conventional rate models and L-CID within the RRKM framework. Using the previously published microcanonical rate data as well as reaction cross-section data, we show that the BDE values obtained with the L-CID model agree with the ones from the other rate models within the expected uncertainty bounds. Based on this agreement, we discuss the possible rationalization of the good performance of the L-CID model.
赖斯-拉姆施佩格-卡塞尔-马库斯（RRKM）理论为计算微正则速率常数提供了一种简单而强大的速率理论。特别是，它已广泛应用于与单分子解离的气相动力学实验相结合，以提取实验键解离能（BDE）。我们之前发现，使用我们名为L-CID的经验速率模型计算得到的BDE值与相应的实验值之间存在一些差异。为了研究我们速率模型的可靠性，我们在RRKM框架内对传统速率模型和L-CID的性能进行了理论分析和比较。利用先前发表的微正则速率数据以及反应截面数据，我们表明，在预期的不确定范围内，L-CID模型得到的BDE值与其他速率模型的结果一致。基于这一一致性，我们讨论了L-CID模型良好性能的可能原因。
