双激发的参考能量:改善和扩展
Fábris Kossoski1, Martial Boggio-Pasqua1, Pierre-François Loos1
1Laboratoire de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France.
Journal of chemical theory and computation
|June 17, 2024
概括
这项研究提高了对双激发状态的准确参考激发能量,这对于理解光诱导化学是至关重要的. 一种新的校正方法可以提高这些具有挑战性的电子转换的计算精度.
科学领域:
- 计算量子化学 计算量子化学
- 摄影化学的使用.
- 理论光谱学 理论光谱学
背景情况:
- 双激发状态,即两个电子同时获得能量,在光化学中至关重要,但在计算上具有挑战性.
- 准确计算这些状态对于理解光物质相互作用和反应机制至关重要.
研究的目的:
- 扩展和完善对双倍激发状态的精确激发能量的基准数据集.
- 评估这些状态的先进电子结构方法的性能.
- 开发一种简单的校正来提高合集群计算的准确性.
主要方法:
- 使用了高阶合集群 (CC3,CCSDT,CC4,CCSDTQ) 和多配置 (CASPT2,CASPT3,PC-NEVPT2,SC-NEVPT2) 的方法.
- 编制了26个分子系统中47个电子转换的数据集,分为"真实"和"部分"双重激发状态.
- 引入了基于从CC3计算中单次激发的百分比 (%T1) 的校正.
主要成果:
- 对"真实"和"部分"双倍激发状态评估各种高级计算方法的准确性.
- 拟议的基于%T1的校正将CC3计算中的错误显著减少三倍.
- 扩展数据集为方法开发和验证提供了更全面的基础.
结论:
- 这项研究为双倍兴奋状态提供了一个有价值的,扩展的激发能量的参考集.
- 开发的校正为提高CC3对这些具有挑战性的状态的可靠性提供了一种实际方法.
- 这项工作将有助于推进激发状态电子结构的计算方法.
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