Li Yu-Lin, Lin Yen-Hsiu, Yin Cangtao, Takahashi Kaito, Chiang Che-Yu, Chang Yuan-Pin, Lin Jim Jr-Min
Institute of Atomic and Molecular Sciences , Academia Sinica , Taipei 10617 , Taiwan.
Department of Chemistry , National Taiwan University , Taipei 10617 , Taiwan.
J Phys Chem A. 2019 May 16;123(19):4096-4103. doi: 10.1021/acs.jpca.8b12553. Epub 2019 May 3.
The kinetics of the reaction of the simplest Criegee intermediate CHOO with CHSH was measured with transient IR absorption spectroscopy in a temperature-controlled flow reaction cell, and the bimolecular rate coefficients were measured from 278 to 349 K and at total pressure from 10 to 300 Torr. The measured bimolecular rate coefficient at 298 K and 300 Torr is (1.01 ± 0.17) × 10 cm s. The results exhibit a weak negative temperature dependence: the activation energy E ( k = Ae) is -1.83 ± 0.05 kcal mol, measured at 30 and 100 Torr. Quantum chemistry calculations of the reaction rate coefficient at the QCISD(T)/CBS//B3LYP/6-311+G(2d,2p) level (1.6 × 10 cm s at 298 K; E = - 2.80 kcal mol) are in reasonable agreement with the experimental results. The experimental and theoretical results of the reaction of CHOO with CHSH are compared to the reactions of CHOO with methanol and hydrogen sulfide, and the trends in reactivity are discussed. The results of the present work indicate that this reaction has a negligible influence to atmospheric CHOO or CHSH.
在温度可控的流动反应池中，采用瞬态红外吸收光谱法测定了最简单的克里奇中间体CHOO与CHSH反应的动力学，并在278至349 K以及10至300 Torr的总压力下测量了双分子速率系数。在298 K和300 Torr下测得的双分子速率系数为(1.01±0.17)×10 cm s。结果显示出较弱的负温度依赖性：在30和100 Torr下测得的活化能E(k = Ae)为-1.83±0.05 kcal mol。在QCISD(T)/CBS//B3LYP/6-311+G(2d,2p)水平下对反应速率系数进行的量子化学计算(298 K时为1.6×10 cm s；E = - 2.80 kcal mol)与实验结果合理吻合。将CHOO与CHSH反应的实验和理论结果与CHOO与甲醇和硫化氢的反应进行了比较，并讨论了反应活性趋势。本工作的结果表明，该反应对大气中的CHOO或CHSH影响可忽略不计。
