单个振幅在ADC(2) 和CC2中对低电子激发状态的单个振幅的作用
Niklas Sülzner1, Christof Hättig1
1Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany.
Journal of chemical theory and computation
|March 7, 2024
概括
配对集群与双重 (CC2) 和代数图形构造 (ADC(2) 方法对具有强配置混合的分子显示偏差. 这项研究分析了solvatochromic染料中的这些差异,揭示了受激发能量和环境影响的显著差异.
科学领域:
- 计算化学是一种计算化学.
- 量子化学是一种量子化学.
- 理论化学是一种理论化学.
背景情况:
- 像CC2和ADC(2) 这样的二阶方法被广泛用于计算有机分子中的单次激发.
- 这些方法通常会产生类似的结果,但由于基本状态和激发状态之间强烈的配置混合,可能会出现差异.
研究的目的:
- 调查和合理化CC2和ADC(2) 方法之间观察到的显著偏差.
- 为了研究配置混合对使用solvatochromic染料这些方法的准确性的影响.
主要方法:
- 采用了CC2和ADC(2) 的计算方法.
- 使用更高层次的CC3计算进行基准比较.
- 在不同的环境极性下研究了两种solvatochromic染料N1-tBu和P1.
主要成果:
- 观察到CC2和ADC之间存在显著的偏差,特别是真空中N1-tBu (0.45 eV的差异).
- 偏差随着极性溶剂激发能量的增加而减少.
- 对于P1,偏差较小,并随着极性而增加,与N1-tBu.Bu相比显示了反向趋势.
- 配置混合程度与不同分子的激发能量大小没有严格的相关性.
结论:
- 强烈的配置混合可以导致CC2和ADC(2) 结果之间存在很大的差异.
- 环境的极性影响观察到的偏差.
- CC2和ADC(2) 的准确性取决于状态,并且需要对具有显著配置相互作用的系统进行仔细考虑.
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