质子与晶体冰相碰撞:在低发射能量下,质子反射和碰撞诱导的水溶解
Pepa Cabrera Sanfelix1, Ayman Al-Halabi, George R Darling
1Surface Science Research Centre, Department of Chemistry, The University of Liverpool, Liverpool L69 3BX, UK.
Journal of the American Chemical Society
|March 18, 2005
概括
由于静电排斥,质子在低能量的冰上令人惊地反射,但在更高的能量时会粘在一起并形成Zundel复合体,导致水分子脱落.
科学领域:
- 物理化学 物理化学
- 表面科学是一门学科.
- 计算物理 计算物理
背景情况:
- 了解离子表面相互作用对于天体化学和等离子体物理学等领域至关重要.
- 质子与冰面相互作用的行为尚未完全理解,特别是在低能量的情况下.
研究的目的:
- 为了研究质子在晶体冰基平面上的粘合动力学.
- 为了确定粘合概率,结合能量和相互作用机制在一系列的发射能量.
主要方法:
- 使用了古典轨迹 (CT) 计算.
- 模拟涵盖了从0.05到4.0 eV的质子发生能.
- 表面温度保持在80K的正常发病率.
主要成果:
- 由于排斥性静电力,在低于0.2 eV的冲击能量下观察到显著的质子反射.
- 粘在一起的概率随着能量增加而增加,能量大于或等于0.8 eV的能量达到单位.
- 质子形成Zundel复合体 (H5O2+),平均结合能量为9.9 eV.
- 质子植入冰面发生,透深度随能量增加.
- 观察到水分子的碰撞诱导的脱吸 ("膨胀"),随着能量增加的概率.
结论:
- 质子-冰相互作用是复杂的,表现出能量依赖的反射和粘合.
- 德尔复合体的形成和随后的水溶解是质子撞击的关键结果.
- 这些发现提供了有关冰体和等离子体环境的表面过程的见解.
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