The reaction of CH₃ + HCNO was theoretically studied by both density functional theory and molecular orbital calculations and analyzed by quantum statistical methods. The potential energy surface was constructed at the UCCSD(T)//B3LYP/6‐311++G(3df,2p) + ZPE level. Four entrance channels are opened relating to the interaction of the CH₃ radical with each of the four atoms of the HCNO molecule, giving rise to 18 different product sets. The predicted geometries and heats of reaction are in good agreement with available experimental data. The major pathways involve addition of CH₃ to the C atom of HCNO with a small energy barrier of ∼4 kcal/mol forming both Z and E‐HC(CH₃)NO (IS1/IS1b) intermediates lying 45 or 44 kcal/mol, respectively, below the reactants. The nascent intermediates can collisionally be deactivated and subsequently decomposed into H + CH₃CNO or isomerized prior to decomposition giving other products. Kinetics calculations covering the temperature range of 400‐2500 K, under pressures of 7.6 × 10^–1 to 7.6 × 10⁵ Torr for N₂, He, and Ar as the third bodies show that at 760 Torr N₂, the adducts including both IS1 and IS1b are the major products at temperature below 600 K, whereas H + CH₃CNO and CNO + CH₄ are the major products at T ≥ 1500 K. The total high‐pressure rate coefficient can well be expressed by the following three‐parameter equation: k(T) = 7.75 × 10^–16 T^1.69 exp (−1480 K/T) cm³ molecule^–1 s^–1.

中文翻译：

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甲基自由基与次膦酸反应中产物通道的预测

 通过密度泛函理论和分子轨道计算对CH ₃ + HCNO的反应进行了理论研究，并通过量子统计方法进行了分析。势能面构造为UCCSD（T）// B3LYP / 6-311 ++ G（3df，2p）+ ZPE水平。与CH ₃自由基与HCNO分子的四个原子中的每个相互作用的四个入口通道被打开，产生18种不同的产物。预测的几何形状和反应热与可用的实验数据高度吻合。主要途径涉及将CH ₃加到HCNO的C原子上，约4 kcal / mol的小能垒形成Z和E- HC（CH ₃NO（IS1 / IS1b）中间体分别位于反应物以下45或44 kcal / mol。新生的中间体可能发生碰撞失活，然后分解为H + CH ₃ CNO或异构化，然后分解为其他产物。 对于N ₂，He和Ar作为第三体，在7.6×10 ^–1至7.6×10 ⁵ Torr的压力下，温度范围为400-2500 K的动力学计算表明，在760 Torr N _2下，加合物包括两种IS1和IS1b是在低于600 K温度的主要产物，而H + CH ₃ CNO和CNO + CH ₄是在主要产物Ť ≥1500K。总高压率系数可以很好地由以下三个参数方程表示：k（T）= 7.75×10 ^–16  T ^1.69 exp（−1480 K / T）cm ³ 分子^–1  s ^{– 1}。