Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Proc Natl Acad Sci U S A. 2012 Jun 26;109(26):10224-7. doi: 10.1073/pnas.1203895109. Epub 2012 Jun 8.
The dissociative chemisorption of water is an important step in many heterogeneous catalytic processes. Here, the mode selectivity of this process was examined quantum mechanically on a realistic potential energy surface determined by fitting planewave density functional calculations spanning a large configuration space. The quantum dynamics of the surface reaction were characterized by a six-dimensional model including all important internal coordinates of H(2)O and its distance to the surface. It was found that excitations in all three vibrational modes are capable of enhancing reactivity more effectively than increasing translational energy, consistent with the "late" transition state in the reaction path.
水的离解化学吸附是许多多相催化过程中的重要步骤。在这里,通过拟合跨越大构型空间的平面波密度泛函计算,从量子力学的角度研究了该过程的模式选择性。表面反应的量子动力学由一个六维模型来描述,该模型包括 H(2)O 的所有重要的内部坐标及其与表面的距离。结果表明,三种振动模式的激发比增加平动能更有效地增强反应活性,这与反应途径中的“后期”过渡态一致。