Gamallo Pablo, Prats Hèctor, Sayós Ramón
Departament de Química Física and Institut de Química Teòrica i Computacional (IQTC-UB), University of Barcelona, C. Martí i Franquès 1, 08028, Barcelona, Spain.
J Mol Model. 2014 Apr;20(4):2160. doi: 10.1007/s00894-014-2160-5. Epub 2014 Mar 16.
A quasiclassical trajectory dynamics study was performed for carbon monoxide collisions over an oxygen preadsorbed β-cristobalite (001) surface. A reactive molecular force field (ReaxFF) was used to model the potential energy surface. The collisions were performed fixing several initial conditions: CO rovibrational states (v = 0-5 and j = 0, 20, 35), collision energies (0.05 ≤ E(col) ≤ 2.5 eV), incident angles (θ(v) = 0°, 45°) and surface temperatures (T(surf) = 300 K, 900 K). The principal elementary processes were the molecular reflection and the non-dissociative molecular adsorption. CO₂ molecules were also formed in minor extension via an Eley-Rideal reaction although some of them were finally retained on the surface. The scattered CO molecules tend to be translationally colder and internally hotter (rotationally and vibrationally) than the initial ones. The present study supports that CO + O(ad) reaction should be less important than O + O(ad) reaction over silica for similar initial conditions of reactants, in agreement with experimental data.
对一氧化碳在预吸附氧的β-方石英（001）表面上的碰撞进行了准经典轨迹动力学研究。使用反应分子力场（ReaxFF）对方能面进行建模。碰撞过程中固定了几个初始条件：CO振转态（v = 0 - 5且j = 0、20、35）、碰撞能量（0.05 ≤ E(col) ≤ 2.5 eV）、入射角（θ(v) = 0°、45°）以及表面温度（T(surf) = 300 K、900 K）。主要的基本过程是分子反射和非解离性分子吸附。尽管一些CO₂分子最终保留在表面，但通过埃利-里德反应也会少量生成CO₂分子。散射后的CO分子在平动上比初始分子更冷，而在内部（转动和振动）更热。本研究表明，在反应物初始条件相似的情况下，在二氧化硅表面上，CO + O(ad)反应应比O + O(ad)反应的重要性更低，这与实验数据一致。
