超出波近似的动量空间中的非波分子动力学:光激发黑中的热电子放松
Haoran Lu1, Wei-Hai Fang1, Run Long1
1College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing 100875, People's Republic of China.
Journal of the American Chemical Society
|July 8, 2024
概括
在黑中模拟热电子放松使用非adiabatic分子动力学 (NA-MD) 与非Condon效应是准确的,即使在大型超级细胞中只有一个k点. 这种高效的方法简化了复杂的光物理研究.
科学领域:
- 凝聚物质物理学
- 材料科学
- 计算化学
背景情况:
- 热电子放松对于了解黑等物质的光物理学至关重要.
- 这些过程的精确模拟需要先进的计算方法.
- 非康登效应和动量空间考虑对于精确的建模很重要.
研究的目的:
- 通过非adiabatic分子动力学 (NA-MD) 在黑中模拟热电子放松的可行性.
- 确定大型超级电池中单个k点的模拟是否可以准确地表示更密集的计算方法的结果.
- 评估这种模拟方法对复杂的光物理现象的效率和适用性.
主要方法:
- 进行了非adiabatic分子动力学 (NA-MD) 模拟.
- 在动量空间中包含非Condon效应.
- 在大型超级细胞中使用单个γ点和小型超级细胞中使用多个k点进行模拟.
- 在相同的能量范围内保持相同数量的电子状态时进行了比较.
主要成果:
- 大型超级电池中的单个k点的模拟结果与小型超级电池中的多个k点的模拟结果一致.
- 无论初始状态能量如何,都能观察到这种一致性.
- 超级细胞大小和k点采样的互补效应被认为是达成协议的原因.
结论:
- 在大型超级细胞中单个k点的模拟是NA-MD非Condon效应的有效和准确近似.
- 这种简化方法有利于研究复杂的光物理,包括间隔散射和间接带隙电荷重组.
- 该方法适用于大型系统,并避免需要和近似,提高计算效率.
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