Kao Tang-Yu, Chung Chen-An, Lee Yuan-Pern
Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
J Phys Chem Lett. 2025 Jun 26;16(25):6455-6462. doi: 10.1021/acs.jpclett.5c01353. Epub 2025 Jun 17.
Reactions between Criegee intermediates and hydrogen halides significantly impact atmospheric chemistry, particularly in polluted urban environments. We employed a multipass absorption flow cell with four probes to determine the rate coefficient of - and -CHCHOO + HCl. Infrared quantum-cascade lasers near 883 and 1280 cm provided temporal profiles of -CHCHOO and a combination of -CHCHOO and the hydrogen-transferred adduct chloroethyl hydroperoxide (CEHP), respectively. A light-emitting diode at 286 nm probed the precursor CHCHI, hence [CHCHI] upon photolysis at 248 nm. Laser light at 335 nm probed both - and -CHCHOO. By modeling the observed temporal profiles, we derived rate coefficients of -CHCHOO + HCl and -CHCHOO + HCl at 298 K as = (5.1 ± 1.1) × 10 cm molecule s and = (2.9 ± 0.8) × 10 cm molecule s, respectively. The latter, previously unreported, is ∼ 5.7 times , highlighting the conformation-specific reactivity.
克里吉中间体与卤化氢之间的反应对大气化学有显著影响，尤其是在污染严重的城市环境中。我们使用了一个带有四个探头的多程吸收流动池来测定 - 和 -CHCHOO + HCl 的速率系数。883 和 12,80 cm 附近的红外量子级联激光器分别提供了 -CHCHOO 以及 -CHCHOO 与氢转移加合物氯乙基过氧化氢（CEHP）的组合的时间分布。一个 286 nm 的发光二极管探测前驱体 CHCHI，从而得到在 248 nm 光解时的 [CHCHI]。335 nm 的激光探测 - 和 -CHCHOO。通过对观测到的时间分布进行建模，我们得出在 298 K 时 -CHCHOO + HCl 和 -CHCHOO + HCl 的速率系数分别为 = (5.1 ± 1.1) × 10 cm³ molecule⁻¹ s⁻¹ 和 = (2.9 ± 0.8) × 10 cm³ molecule⁻¹ s⁻¹。后者此前未被报道，约为 的 5.7 倍，突出了构象特异性反应活性。
