在单晶表面的Pt{\displaystyle Pt}{\displaystyle Pt}{\displaystyle Pt}{\displaystyle Pt}{\displaystyle Pt}{\displaystyle
Françoise Delbecq1, Francisco Zaera
1Department of Chemistry, University of California, Riverside, California 92521, USA.
Journal of the American Chemical Society
|October 22, 2008
概括
密度功能理论 (DFT) 的计算解释了为什么在金表面上转化为cis-2-butene. 在cis同位素吸附过程中,较低分子重组和表面重建驱动了这种选择性.
科学领域:
- 表面科学是一门学科.
- 催化剂是一种催化剂.
- 计算化学计算化学
背景情况:
- 基在金属表面的转化在催化过程中至关重要.
- 之前的研究发现,从Pt上的trans-2-butene中形成较不稳定的cis-2-butene异构体的意想不到的偏好.
研究的目的:
- 阐明底层机制和控制在Pt{111}表面上从trans{2}-butene中选择性形成cis{2}-butene的因素.
- 用理论计算来解释观察到的反应选择性.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 分析的重点是Pt上的吸附能量和表面过程.
主要成果:
- DFT计算显示,cis异构体的吸附需要较少的分子重新排列,而不是覆盖Pt上的trans异构体.
- 表面重建对于cis异构体的吸附也不那么重要.
- 这些因素有助于观察到对cis-2-butan形成的偏好.
结论:
- 覆盖和表面原子重组是吸附能量和反应选择性的关键决定因素.
- 这些发现为不稳定的cis同位素的优先合成提供了理论解释.
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