The hydrogen abstraction reactions from hydrazine and its methyl derivatives by the H atom have been investigated theoretically by using CBS‐QB3//DSD‐BLYP‐D3(BJ)/Def2‐TZVP quantum chemical calculations and transition state theory calculations coupled with various tunneling correction methods. Both the products and transition state energies of the hydrogen abstraction from the amino group were stabilized by the methyl group substitution. The substitution effect on the ^αN site was two times larger than that on the ^βN site. On the other hand, the substitution effect was negligible on the hydrogen abstraction from the methyl group. The overall rate coefficients of N₂H₄ + H reaction calculated by canonical variational transition state theory with the small‐curvature tunneling correction agreed well with previously reported values, but those of CH₃NHNH₂/(CH₃)₂NNH₂ + H were slightly lower than a previous experimental value. The product‐specific rate coefficients have been proposed for the kinetics modeling of these fuels’ combustion.

中文翻译：

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H原子从肼衍生物夺氢反应的理论研究

通过使用CBS-QB3 // DSD-BLYP-D3（BJ）/ Def2-TZVP量子化学计算和过渡态理论计算以及各种隧穿校正理论研究了H原子从肼及其甲基衍生物中夺氢的反应方法。氨基取代氢的产物和过渡态能量都通过甲基取代而稳定。在替代效应^α n个站点比在大两倍^β n个站点。另一方面，从甲基提取氢的取代作用可以忽略。N ₂ H ₄的总比率系数通过标准变分过渡态理论计算的+ H反应，采用小曲率隧道校正，与先前报道的值非常吻合，但CH ₃ NHNH ₂ /（CH ₃）₂ NNH ₂ + H的+ H反应略低于先前的实验值。已经提出了针对产品的速率系数，用于这些燃料燃烧的动力学模型。