Wang Huan-Jiang, Wang Yong-Cheng
College of Bo Wen, Lanzhou Jiaotong University, Lanzhou, Gansu, 730070, China.
J Mol Model. 2014 Jun;20(6):2301. doi: 10.1007/s00894-014-2301-x. Epub 2014 Jun 4.
Carbon monoxide (CO) and oxygen (O2) catalyzed by small neutral iron oxide clusters (FeO(1-3)) was investigated at the density functional level of theory using the Becke-Perdew-Wang functional (BPW91). Three reaction pathways along with singlet, triplet and quintet states were calculated for ascertaining the presence of some spin inversion during the catalytic cycle. The catalytic cycle was found to be "two state reactivity" resulting from the crossing among the multistate energetic profiles. The Landau-Zener equation was used to calculate the thermally-averaged spin transition probabilities for the non-adiabatic surface crossing reaction. In order to predict the efficiency of catalyst the energetic span model developed by Kozuch was implemented, whereas this model is not suitable for handling the diabatic reaction, this feature we must take into consideration. To this end, a kinetic assessment is carried out with an expansion of the energetic span model, including the spin-crossing effects. This approximation enables one to measure the efficiency of catalytic cycle including spin-crossing effects by quantum mechanical computation.
在密度泛函理论水平下，使用Becke-Perdew-Wang泛函（BPW91）研究了由小的中性氧化铁簇（FeO(1-3)）催化的一氧化碳（CO）和氧气（O₂）反应。计算了单重态、三重态和五重态的三条反应路径，以确定催化循环中是否存在自旋反转。发现催化循环是由多态能量分布之间的交叉导致的“双态反应性”。利用朗道-齐纳方程计算非绝热表面交叉反应的热平均自旋跃迁概率。为了预测催化剂的效率，采用了Kozuch开发的能量跨度模型，然而该模型不适用于处理非绝热反应，我们必须考虑这一特性。为此，通过扩展能量跨度模型进行动力学评估，包括自旋交叉效应。这种近似使得人们能够通过量子力学计算来测量包括自旋交叉效应的催化循环效率。
