在过渡潜力合集群的功能依赖性上
Alexis Antoinette Ann Delgado1, Devin A Matthews1
1Department of Chemistry, Southern Methodist University, Dallas, Texas 75275, USA.
The Journal of chemical physics
|June 25, 2025
概括
过渡-潜在合集群 (TP-CC) 方法通过考虑轨道放松,准确计算核心电离和激发能量. 用于生成TP-CC计算轨道的不同密度函数为K边缘光谱产生了可比,准确的结果.
科学领域:
- 量子化学 是一个量子化学.
- 计算光谱学是一种计算光谱学.
- 电子结构理论 电子结构理论
背景情况:
- 核电离和激发能量在光谱学中至关重要,但由于轨道放松,通常会出现计算错误.
- 过渡潜力合集群 (TP-CC) 方法提供了一种方法,通过使用部分占用轨道来明确解决轨道放松问题.
研究的目的:
- 评估各种密度函数对核心层次光谱的TP-CC计算准确性的影响.
- 确定是否选择用于生成部分占用轨道的函数影响TP-CC结果的可靠性.
主要方法:
- 使用过渡潜力合集群 (TP-CC) 方法,特别是TP-CCSD和XTP-CCSD.
- 通过几个密度函数 (HF,BP86,BH&HLYP,B3LYP,M06-2X, ωB97m-V) 生成的利用了部分占用的轨道.
- 计算了有机K边缘X射线吸收和光电子光谱.
主要成果:
- 在所有测试密度函数中,TP-CC计算产生了准确且可比的核心电离能,核心激发能和振荡器强度.
- 选择用于生成最初部分占用轨道的函数并没有显著影响最终TP-CCSD结果.
结论:
- 对于生成分数占用轨道的密度函数选择对 K 边缘光谱的 TP-CC 计算的准确性影响很小.
- TP-CC方法为核心层次光谱学提供了强大而可靠的计算工具,不管先前的功能选择如何.
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