对分子有机晶体中激发状态的点电荷嵌入方案的性能
Amir Sidat1, Michael Ingham2, Miguel Rivera2
1School of Physical and Chemical Sciences, Queen Mary University of London, London, United Kingdom.
The Journal of chemical physics
|December 27, 2023
概括
这项研究评估了嵌入模型,用于预测分子晶体激发状态. 结果指导材料科学中光学差距的准确建模.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 模拟分子晶体中的兴奋状态对于有机电子等应用至关重要.
- 嵌入点电费的集群模型是一种常见但复杂的方法.
- 精确预测激发状态和光学间隙仍然具有挑战性.
研究的目的:
- 为了比较各种嵌入模型在分子晶体中激发状态计算的性能.
- 评估不同理论水平,基础集和嵌入方案的影响.
- 研究在晶体模型中减轻过极化和电荷泄漏的方法.
主要方法:
- 评估了集群模型,Ewald嵌入和自我一致的嵌入方法.
- 采用了各种层次的理论:时间依赖密度函数理论 (TDFT) 与TDA,CC2,CASSCF和CASPT2.
- 使用的DFT函数为 ωB97X-D 和 PBE0.0.
- 实施了距离值方案,以解决电荷泄漏和过度极化问题.
主要成果:
- 基于基本和激发状态的原子电荷方案进行比较.
- 分析了QM区域大小,电荷泄漏和理论水平对激发状态描述的影响.
- 嵌入模型的性能与实验数据和其他高级计算方法 (G0W0-BSE,定期TDA) 相比进行了基准测试.
结论:
- 该研究提供了嵌入模型的全面比较,用于分子晶体中激发状态计算.
- 结果为选择适当的方法和参数提供了准确的光学间隙预测的指导.
- 开发的策略可以提高分子晶体应用的计算建模的可靠性.
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