弥合基于DFT的变化和扰动方法之间的差距,用于计算激发状态
Andrey Sinyavskiy1, Momir Mališ1, Sandra Luber1
1Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
Journal of chemical theory and computation
|July 22, 2025
概括
限制开放的Kohn-Sham三角洲自相一致场 (ROKS-ΔSCF) 方法可以在没有自旋净化的情况下准确计算激发的电子状态. 本研究将ROKS-ΔSCF与时间依赖密度函数理论 (TDDFT) 对激发能和特性进行基准测试.
科学领域:
- 量子化学是一种量子化学.
- 计算物理学的计算物理.
- 理论化学是一种理论化学.
背景情况:
- 德尔塔自相一致场 (ΔSCF) 方法对于计算电子激发状态至关重要.
- 现有的方法可能需要复杂的旋转净化程序.
- 限制开放的Kohn-Sham (ROKS) 形式主义为针对特定电子状态提供了一个潜在的替代方案.
研究的目的:
- 详细研究基于 ROKS 的 ΔSCF 方法,用于计算未混合单点兴奋电子状态.
- 提出修改,以提高 ΔSCF 方法的趋同性和稳定性.
- 为了对ROKS-ΔSCF与激发状态的时间依赖密度函数理论 (TDDFT) 进行比较.
主要方法:
- 基于 ROKS 的 ΔSCF 方法的实施和应用.
- 修改最大重叠方法以改善 ΔSCF 趋同.
- 开发一个分子轨道跟踪和保持秩序的算法.
- 与TDDFT进行激发能,电子密度和过渡双极瞬间的大规模比较.
主要成果:
- ROKS-ΔSCF方法成功地准未混合的单片激发状态,消除了对自旋净化的需求.
- 经过修改的算法证明了 ΔSCF 计算的更好的趋同.
- ROKS-ΔSCF的结果与TDDFT在各种分子的激发能量和特性方面有很好的一致性.
- 通过ROKS-ΔSCF方法复制了单基和多基激发状态.
结论:
- 基于ROKS的ΔSCF是一种可行且高效的方法,用于计算激发电子状态,特别是未混合的单片.
- 提出的算法改进提高了 ΔSCF 方法的实际适用性.
- ROKS-ΔSCF作为TDDFT研究兴奋状态属性的可靠替代品.
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