当前位置：
X-MOL 学术
›
J. Phys. Chem. A
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Double Hydrogen-Atom Exchange Reactions of HX (X = F, Cl, Br, I) with HO2
The Journal of Physical Chemistry A ( IF 2.7 ) Pub Date : 2018-05-24 00:00:00 , DOI: 10.1021/acs.jpca.8b01602 Jonathan R. Church 1 , Rex T. Skodje 1
The Journal of Physical Chemistry A ( IF 2.7 ) Pub Date : 2018-05-24 00:00:00 , DOI: 10.1021/acs.jpca.8b01602 Jonathan R. Church 1 , Rex T. Skodje 1
Affiliation
|
A novel double hydrogen atom exchange process, HX + H′O2 → H′X + HO2 for the halogen series X = F, Cl, Br, and I, is identified using theoretical methods. These concerted reactions are mediated through a stabilized five-membered planar ring transition state structure. The transition state barrier for the double exchange process is found to be significantly lower than that for the abstraction reaction of a single hydrogen atom. Density functional theory employing the M11 exchange functional is used to compute parameters of the potential energy surface and the rate coefficients are obtained using transition state theory with small curvature tunneling. For low temperatures, the exchange reaction proceeds at a rate several orders of magnitude faster than the abstraction channel, which is also calculated. The exchange process may be observed using isotope scrambling reactions; such reactions may contribute to observed isotope abundances in the atmosphere. The rate coefficients for the isotopically labeled reactions are computed. It is found that the trends in reactivity within the series of halogen reactions can be quantitatively understood using the degree of electron delocalization at the transition state. The barriers are found to fall as the electronegativity of the halogen atom decreases.
中文翻译：
HX（X = F，Cl，Br，I）与HO 2的双氢原子交换反应
一种新颖的双氢原子交换过程，HX + H'O 2 → H'X + HO 2对于卤素系列，X ＝ F，Cl，Br和I的确定是使用理论方法确定的。这些一致的反应是通过稳定的五元平面环过渡态结构介导的。发现双交换过程的过渡态势垒明显低于单个氢原子的抽象反应的过渡态势垒。使用采用M11交换函数的密度泛函理论来计算势能面的参数，并使用具有小曲率隧穿的过渡态理论来获得速率系数。对于低温，交换反应以比提取通道快几个数量级的速率进行，提取通道也被计算出来。交换过程可以通过同位素加扰反应观察到。这样的反应可能有助于观测到的大气中的同位素丰度。计算同位素标记反应的速率系数。发现使用过渡态的电子离域度可以定量地理解一系列卤素反应中反应性的趋势。发现势垒随着卤素原子的电负性降低而降低。
更新日期：2018-05-24
中文翻译：
HX（X = F，Cl，Br，I）与HO 2的双氢原子交换反应
一种新颖的双氢原子交换过程，HX + H'O 2 → H'X + HO 2对于卤素系列，X ＝ F，Cl，Br和I的确定是使用理论方法确定的。这些一致的反应是通过稳定的五元平面环过渡态结构介导的。发现双交换过程的过渡态势垒明显低于单个氢原子的抽象反应的过渡态势垒。使用采用M11交换函数的密度泛函理论来计算势能面的参数，并使用具有小曲率隧穿的过渡态理论来获得速率系数。对于低温，交换反应以比提取通道快几个数量级的速率进行，提取通道也被计算出来。交换过程可以通过同位素加扰反应观察到。这样的反应可能有助于观测到的大气中的同位素丰度。计算同位素标记反应的速率系数。发现使用过渡态的电子离域度可以定量地理解一系列卤素反应中反应性的趋势。发现势垒随着卤素原子的电负性降低而降低。
京公网安备 11010802027423号