和与H-Si的表面反应:密度函数理论研究研究
Noboru Takeuchi1, Yosuke Kanai, Annabella Selloni
1Department of Chemistry, Princeton University, Princeton, New Jersey 08540, USA. takeuchi@princeton.edu
Journal of the American Chemical Society
|December 2, 2004
概括
将某些分子添加到表面可以触发连锁反应,形成稳定的吸附物种. 这种反应对于某些分子是可行的,但对于其他分子则不那么可行,这取决于它们的化学结构.
科学领域:
- 表面化学 表面化学
- 材料科学是一种材料科学.
- 计算化学是一种计算化学.
背景情况:
- 表面在半导体技术中至关重要.
- 了解表面反应是开发新材料和新工艺的关键.
- 在表面添加基和基可以启动复杂的反应路径.
研究的目的:
- 研究H端表面连锁反应的初始步骤.
- 确定不同基和基分子的链机制的可行性.
- 阐明影响稳定吸附物种形成的因素.
主要方法:
- 使用周期密度函数理论 (DFT) 的计算.
- 使用了一种有效的方法来确定反应路径.
- 计算了Si上的各种分子的最小能量通路 (MEP).
主要成果:
- 链式机制对于乙 (C(2) H(2) 是可行的.
- 乙烯 (C(2) H(4)) 由于中间稳定性较低和高的H抽象障碍,更有可能去吸收.
- 乙烯和 styrene 显示中间稳定和减少 H-抽象障碍,形成稳定的物种,具有较高的吸附热量为基.
结论:
- 表面连锁反应的可行性取决于特定的烯或烯分子.
- 分子结构显著影响中间稳定性和反应障碍.
- 与类对应物相比,类,如乙烯,具有较大的稳定吸附潜力.
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