Chemical Engineering, School of Engineering, Brown University, Providence, Rhode Island 02912, United States.
J Phys Chem A. 2023 Feb 16;127(6):1499-1511. doi: 10.1021/acs.jpca.2c06623. Epub 2023 Feb 6.
A new detailed chemical kinetic mechanism is presented for small fluorinated hydrocarbons. Ab initio electronic structure theory is used to provide heats of formation with subchemical accuracy. The ANL0 method is extended to include fluorine. The resulting heats of formation at 0 K are in excellent agreement with 36 benchmark species in the Active Thermochemical Tables, with a mean error of μ = -0.02 kJ/mol and a standard deviation of σ = 0.91 kJ/mol. The thermophysical properties for 92 small-molecule H/C/O/F species are computed. The rate coefficients for 40+ H-abstraction reactions involving H, O, F, OH, OF, HO, and various methyl radicals with CH, CHF, CHF, CHF, CHO, and CHFO are discussed. The computed rate constants are in excellent agreement with the available literature. Additionally, 30+ rate constants are provided for F abstraction, which are several orders of magnitude smaller than H abstraction. The thermophysical properties and rate constants are provided in a mechanism. This mechanism is the first in a series of theory-based investigations into the thermal destruction of per- and polyfluorinated species.
本文提出了一个新的详细的含氟小分子化学动力学机制。从头算电子结构理论被用来提供亚化学精度的生成焓。ANL0 方法被扩展到包括氟。由此得到的 0 K 下的生成焓与活性热化学表中的 36 个基准物种非常吻合，平均误差 μ = -0.02 kJ/mol，标准偏差 σ = 0.91 kJ/mol。计算了 92 种小分子 H/C/O/F 物种的热物理性质。讨论了 40 多个涉及 H、O、F、OH、OF、HO 和各种甲基自由基与 CH、CHF、CHF、CHF、CHO 和 CHFO 的 H 抽提反应的速率系数。计算得到的速率常数与现有文献非常吻合。此外，还提供了 30 多个 F 抽提的速率常数，它们比 H 抽提小几个数量级。热物理性质和速率常数以一个机理的形式呈现。该机理是一系列基于理论的全氟和多氟物种热破坏研究的第一个。
