高碰撞能量的气体表面化学反应?
Michael J Gordon1, Xiangdong Qin, Alex Kutana
1Department of Chemical Engineering, University of California Santa Barbara, California 93106-5080, USA.
Journal of the American Chemical Society
|February 5, 2009
概括
能量离子 (F(+)) 对化表面的冲击会产生超快的F(2)(-) 分子. 这种新的多步机制产生了具有高动能的超热产品.
科学领域:
- 表面科学是一门科学.
- 化学物理 化学物理
- 材料科学是一种材料科学.
背景情况:
- 气体表面反应通常产生低能产物.
- 能量弹子可以诱导高热产品的形成.
研究的目的:
- 为了研究表面的能量离子轰炸产生的超快分子产物的形成.
- 为了阐明超热F的背后的机制.
主要方法:
- 化银 (Ag) 和 (Si) 表面用离子 (F(+)) 在30-300 eV的能量范围内进行轰炸.
- 对产生的分子产品的动能进行分析.
主要成果:
- 发现"超快"的F(2)(-) 分子产品,其输出能量高达90 eV.
- 确定一个多步直接反应机制,负责高热产品的形成.
- 确认弹子F原子被纳入快速的F(2)(-) 产物.
结论:
- 能量F(+) 轰炸可以通过一种新的多步机制驱动高热F(2)(-) 的形成.
- 这一过程允许创建高能分子产品,即使冲击能量超过典型的键能.
- 这些发现挑战了在能量条件下对气体表面反应动态的传统理解.
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