在激发状态中探索非共价相互作用:超越芳香性排泄物模型
1School of Chemistry, The University of Melbourne, Parkville, Australia. lars.goerigk@unimelb.edu.au.
Physical chemistry chemical physics : PCCP
|September 24, 2024
概括
时间依赖密度函数理论 (TD-DFT) 方法通常是由于缺少分散力而导致兴奋状态复合体的基础. 添加像D3 ((BJ) 这样的分散校正可以显著提高这些非共价相互作用的准确性.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 时间依赖密度函数理论 (TD-DFT) 是一种具有成本效益的激发状态计算方法.
- 传统的TD-DFT很难准确地描述非共价相互作用 (NCIs),类似于地面状态的DFT.
- 精确的兴奋状态NCIs的建模对于理解exciplex行为至关重要.
研究的目的:
- 为了对各种TD-DFT方法进行基准测试,以确定它们在描述激发状态非共价相互作用 (NCIs) 中的准确性.
- 为了评估基态分散校正 (DFT-D3(BJ,VV10) 对TD-DFT计算外向结合能量的影响.
- 确定最可靠的TD-DFT方法,用于模拟不同激发类型和几何形状的exciplexes.
主要方法:
- 计算模型外接曲线的解离曲线,以评估结合强度.
- 将TD-DFT方法与高级波函数计算进行比较 (SCS-CC2/CBS(3,4)).
- 在TD-DFT计算中包括和评估DFT-D3 (BJ) 和VV10分散校正.
主要成果:
- 在TD-DFT方法中,通常会结合exciplexes,主要是因为忽略了分散力.
- 散射校正,特别是 DFT-D3 ((BJ),对于在外向结合能量中获得良好的精度至关重要.
- VV10型非局部内核显示出希望,但主要影响基态能量;双混合功能 (B2GP-PLYP-D3(BJ,B2PLYP-D3(BJ)) 对于局部激发是强大的.
结论:
- 基态分散校正对于准确的TD-DFT描述外结合至关重要.
- 带有分散校正的双杂交函数为具有局部激发的exciplexes提供可靠的性能.
- 未来的改进需要解决TD-DFT中对特定状态的分散校正的需求.
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