在有机半导体中的电荷传输从映射方法到表面跳跃
Johan E Runeson1, Thomas J G Drayton1, David E Manolopoulos1
1Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom.
The Journal of chemical physics
|October 8, 2024
概括
我们介绍了一种新的量子经典方法,用于模拟有机半导体中的电荷扩散. 这种方法提高了统计趋同,并产生了准确的移动性值,比较高的表现较旧的近似.
科学领域:
- 计算物理学的计算物理.
- 材料科学 是一种材料科学.
- 量子力学就是量子力学.
背景情况:
- 在有机半导体中模拟电荷扩散对于理解电荷传输至关重要.
- 现有的方法,如最少开关的表面跳跃在保持平衡分布方面存在局限性.
- 精确的模拟需要对量子力学和经典力学进行一致的处理.
研究的目的:
- 引入和验证一种混合量子-经典方法,即绘图方法对表面跳跃 (MASH),用于模拟电荷扩散.
- 证明MASH能够保持平衡分布并改善统计趋同的能力.
- 将MASH衍生的电荷流动性与现有方法进行比较.
主要方法:
- 在量子古典模拟中使用地图方法进行表面跳跃 (MASH).
- 在人口最多的电子状态上决定性地传播经典的自由度.
- 沿轨迹进行时间平均,以增强统计趋同.
主要成果:
- 马什方法正确地保持了与古典声子相结合的量子电荷的平衡分布.
- 获得了依赖时间的扩散系数,该系数与长时间的极限值相平衡.
- 在晶体中计算的移动性高于放松时间近似值,类似于Ehrenfest动态.
结论:
- 表面跳跃的映射方法是模拟有机半导体中电荷扩散的一致和准确方法.
- 通过保持平衡分布,MASH克服了标准的表面跳跃方法的局限性.
- 该方法为计算电荷流动性提供了可靠的途径,为有机电子材料性能提供了洞察力.
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