A multidimensional study of the reaction CH2I+O2: products and atmospheric implications.
A multidimensional study of the reaction CH2I+O2: products and atmospheric implications.
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CH2I O2 反应的多维研究：产物和大气影响。
DOI：
10.1002/cphc.201000575
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
D. Heard
中科院分区：
文献类型：
--
作者：
T. Gravestock;M. Blitz;W. Bloss;D. Heard
用激光闪光光解、吸收光谱、激光诱导荧光光谱和质谱法研究了CH2I+O2的反应。在准一级条件下，IO和CH(2)O的生成速率依赖于CH(2)I(2)的浓度([O(2)]≫[CH(2)I(2)])，这表明IO和CH(2)O不是直接由标题反应生成的，这与Enami等人最近的研究相反。提出了反应是通过生成过氧基物种CH(2)IO(2)进行的，该物种发生自反应生成CH(2)IO并分解为CH(2)O+I，在实验室体系中IO是通过I+CH(2)IO(2)反应形成的。在310400 nm范围内观察到一种归属于CH(2)IO(2)的物种的吸收光谱，最大吸收波长为327.2 nm，最大吸收波长为σ≥1.70×10(-18)cm(-1)分子。模拟研究表明，CH(2)IO(2)+CH(2)IO(2)自反应和I+CH(2)IO(2)反应的室温速率系数分别控制在(6-12)×10(-11)cm(3)分子(-1)S(-1)和(1-2)×10(-11)cm(3)分子(-1)S(-1)的范围内。在大气中，CH(2)IO(2)会与其他自由基缓慢反应，释放出碘原子，碘原子再与臭氧反应生成IO。IO的缓慢形成意味着形成较低的浓度，这导致较低的倾向形成粒子，因为前体分子OIO以依赖于IO浓度的平方的速度形成。
The CH(2)I+O(2) reaction has been studied using laser flash photolysis followed by absorption spectroscopy, laser-induced fluorescence spectroscopy and mass spectrometry. The rates of formation of IO and CH(2)O were found to be dependent upon the concentration of CH(2)I(2) under pseudo-first-order conditions ([O(2)]≫[CH(2)I(2)]), demonstrating that IO and CH(2)O are not formed directly from the title reaction, in contrast to recent investigations by Enami et al. It is proposed that the reaction proceeds via the formation of the peroxy radical species CH(2)IO(2), which undergoes self-reaction to form CH(2)IO, and which decomposes to CH(2)O+I, and that in laboratory systems IO is formed via the reaction I+CH(2)IO(2). The absorption spectrum of a species assigned to CH(2)IO(2) was observed in the range 310-400 nm with a maximum absorption at 327.2 nm of σ≥1.7×10(-18) cm(2) molecule(-1). A modelling study enabled the room temperature rate coefficients for the CH(2)IO(2)+CH(2)IO(2) self-reaction and the I+CH(2)IO(2) reaction to be confined within the ranges (6-12)×10(-11) cm(3) molecule(-1) s(-1), and (1-2)×10(-11) cm(3) molecule(-1) s(-1), respectively. In the atmosphere, CH(2)IO(2) will slowly react with other radicals to release iodine atoms, which can then form IO via reaction with ozone. Slow formation of IO means that lower concentrations are formed, which leads to a lower propensity to form particles as the precursor molecule OIO forms at a rate which is dependent on the square of the IO concentration.
影响因子：
64.8
作者：
Read, Katie A.;Mahajan, Anoop S.;Plane, John M. C.
通讯作者：
Plane, John M. C.
影响因子：
5.2
作者：
Martino, Manuela;Mills, Graham P.;Liss, Peter S.
通讯作者：
Liss, Peter S.
碘介导的沿海颗粒形成：海洋边界层中的活性卤素 (RHaMBLe) 概述 Roscoff 沿海研究
DOI：
10.5194/acpd-9-26421-2009
发表时间：
2009
期刊：
--
影响因子：
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作者：
McFiggans G
通讯作者：
McFiggans G