The multichannel reaction of excited singlet oxygen atom with ethanol, O(¹D) + C₂H₅OH (1), was studied in a photolysis flow reactor coupled with mid‐infrared Faraday rotation spectroscopy (FRS) and UV‐IR direct absorption spectroscopy (DAS) at 297 K with reactor pressures of 60, 120, and 150 Torr (bath He). The excited singlet oxygen atom was generated through the photolysis of O₃ at 266 nm. The photon flux and O(¹D) concentrations were determined by in situ actinometry based on O₃ depletion. Temporal profiles of OH and H₂O were monitored via DAS signals at ca. 3568.62 and 3568.29 cm⁻¹, while temporal profiles of HO₂ were measured via FRS signals at ca. 1396.90 cm⁻¹. The branching ratios of the target reaction (1) were determined by fitting temporal profiles to simulations from an in‐house reaction mechanism. Two major reaction channels were identified as CH₃CHOH + OH and CH₃O + CH₂OH, and their branching ratios were determined as 0.46 ± 0.12 and 0.42 ± 0.11, respectively. A specific HO₂ + RO₂ reaction between HO₂ and O₂CH₂CH₂OH (β‐RO₂) at the low‐temperature range is estimated in this work as HO₂ + O₂CH₂CH₂OH products with a rate constant of 7 × 10⁻¹² cm³ molecule⁻¹ s⁻¹.

中文翻译：

---

乙醇激发单线态氧原子O（1D）反应的动力学研究

在结合中红外法拉第旋转光谱（FRS）和UV-IR直接吸收的光解流反应器中研究了激发的单线态氧原子与乙醇O（¹ D）+ C ₂ H ₅ OH（1）的多通道反应297 K时的光谱（DAS），反应器压力分别为60、120和150托（He浴）。激发的单线态氧原子是通过O ₃在266 nm处的光解而产生的。光子通量和O（¹ D）浓度是通过基于O ₃耗尽的原位光化法测定的。OH和H ₂ O的时间分布图通过DAS信号在大约₂₀ ℃进行监测。3568.62和3568.29 cm ^-1，而HO _2的时间剖面通过FRS信号在大约 1396.90厘米^-1。目标反应（1）的支化比是通过将时间曲线拟合到内部反应机理的模拟中来确定的。确定了两个主要反应通道：CH ₃ CHOH + OH和CH ₃ O + CH ₂ OH，其支化比分别确定为0.46±0.12和0.42±0.11。具体HO ₂ + RO ₂ HO之间反应₂和O ₂ CH ₂ CH ₂ OH（β-RO ₂）在低温度范围内，估计在此工作如HO ₂ + O ₂ CH速率常数为7×10 ^-12 cm ³分子^-1 s ^-1的₂ CH ₂ OH产物。