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Image-based Lagrangian Particle Tracking in Bed-load Experiments
Published on: July 20, 2017
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在表面跳跃方法中保持线性和角运动量
Yanze Wu1, Jonathan Rawlinson2, Robert G Littlejohn3
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
The Journal of chemical physics
|January 11, 2024
概括
标准的最少开关表面跳跃算法未能在具有自旋轨道合和奇数电子的系统中保持动量. 一个解决方案涉及使用相空间电子哈密尔顿数来确保半经典模拟中的动量保存.
科学领域:
- 量子化学 是一个量子化学.
- 计算化学计算化学
- 理论化学 理论化学
背景情况:
- 最少开关表面跳跃 (FSSH) 是模拟非adiabatic动态的标准算法.
- 具有自旋轨道合和奇数电子的系统为FSSH带来了独特的挑战.
- 保持线性和角动量对于准确的模拟至关重要.
研究的目的:
- 为了确定标准FSSH算法的限制在节省动量方面.
- 为准确的半古典模拟提出一个修改后的方法.
- 解决核,电子轨道和电子自旋自由度的合.
主要方法:
- 对具有自旋轨道合的系统在FSSH中的动量保存的分析.
- 在亚亚巴特动力学中对时间可逆性的研究.
- 使用相空间电子哈密尔顿数H (R,P) 开发解决方案.
主要成果:
- 标准的FSSH算法在特定系统中违反了线性和角动量保护.
- 这种违规行为源于沿着非时间可逆的表面传播动态.
- 沿相空间电子哈密尔顿的固有值运行动力学与特定的电子-核合解决了这个问题.
结论:
- 修改后的半经典方法是必要的准确的模拟涉及合的核,电子轨道和旋转动力学.
- 使用相空间哈密尔顿的拟议方法为改进的模拟提供了途径.
- 这项工作对于表现出奇拉诱导旋转选择性的系统是相关的.
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