深波段电子对的低能离子阻断功率的贡献
F Matias1, P L Grande2, N E Koval3
1Instituto de Pesquisas Energéticas e Nucleares, Av. Professor Lineu Prestes, São Paulo 05508-000, Brazil.
The Journal of chemical physics
|August 13, 2024
概括
精确计算了中离子的电子停止截面. 通过包括更深层的带电子来解决与实验的差异,揭示了低速度活跃的机制.
科学领域:
- 材料科学 材料科学 材料科学
- 原子和分子物理 原子和分子物理
- 计算物理 计算物理
背景情况:
- 实验研究显示,中离子的电子阻断截面存在差异.
- 密度函数理论 (DFT) 的估计并不完全与低到中等能量范围的观测值保持一致.
研究的目的:
- 为中H,He,N和Ne的电子停止截面提供准确的理论结果.
- 解决DFT计算和实验发现之间的差异.
- 为了研究较深的带在离子能量损失中的作用.
主要方法:
- 使用的非扰动理论方法:实时时间依赖密度函数理论 (RT-TDDFT),运输截面和诱导密度方法.
- 纳入了较深的波段的不均电子密度.
- 分析的离子速度接近零 (v → 0).
主要成果:
- 精确的电子停止截面得到了中的H,He,N和Ne.
- 通过考虑更深波段电子贡献来解决DFT和实验数据之间的差异.
- 有证据表明",升降机"和"提升"机制是活跃的,影响离子能量损失.
结论:
- 包含更深的带电子对于准确建模低速电子停止截面至关重要.
- 在非常低的速度下,速度比例的崩是深波段电子贡献的标志.
- 理论模型必须考虑这些深波段效应,以完全模拟材料中的离子能量损失.
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