Zou Chan, Wang Chunbo
Department of Energy Power & Mechanical Engineering, North China Electric Power University, Baoding, 071003, China.
J Mol Model. 2019 Jan 7;25(2):30. doi: 10.1007/s00894-018-3916-0.
The reactions between arsenic and nitrogen oxides (NO, NO, and NO) were investigated using density functional theory. The geometries of the reactants, intermediates, transition states, and products in each reaction were optimized. Frequency analysis was applied to verify those geometries, and the authenticity of each transition state was checked using intrinsic reaction coordinate analysis (IRC). The single point energy of each stationary point was calculated at the B2PLYP level, and kinetic analysis was conducted to explore each reaction mechanism in more detail. Results showed that the energy barriers to the reactions of As with NO, NO, and NO were 78.45, 2.58, and 155.85 kJ mol, respectively. For each reaction, the rate increased as the temperature was increased from 298 to 1800 K. However, temperature had only a tiny impact on the reaction of As with NO due to the low energy barrier involved, and the reaction rate was consistently high (>10 cm mol s), which indicates that this reaction occurs readily. On the other hand, the rate of the reaction between As and NO or NO increased rapidly between 298 and 900 K, and then increased more gradually upon further increasing the temperature.
采用密度泛函理论研究了砷与氮氧化物（NO、NO₂和N₂O）之间的反应。优化了各反应中反应物、中间体、过渡态和产物的几何结构。应用频率分析来验证这些几何结构，并使用内禀反应坐标分析（IRC）检查每个过渡态的真实性。在B2PLYP水平上计算了每个驻点的单点能量，并进行了动力学分析以更详细地探索各反应机理。结果表明，砷与NO、NO₂和N₂O反应的能垒分别为78.45、2.58和155.85 kJ/mol。对于每个反应，随着温度从298 K升高到1800 K，反应速率增加。然而，由于涉及的能垒较低，温度对砷与NO反应的影响很小，反应速率一直很高（>10⁻⁵ cm³ mol⁻¹ s⁻¹），这表明该反应很容易发生。另一方面，砷与NO₂或N₂O之间的反应速率在298 K至900 K之间迅速增加，然后在进一步升高温度时增加得更为缓慢。
