注意差距:STGABS27集可以教导什么关于二次激发状态方法,溶剂模型和电荷转移
Thomas Froitzheim1, Christof Hättig2, Jan-Michael Mewes1,3
1Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany.
Physical chemistry chemical physics : PCCP
|August 26, 2025
概括
在有机电子产品中精确计算单元-三元差距是具有挑战性的. 与DFT方法相比,旋转尺度的ADC(2) 或CC2具有特定的溶解模型,但在计算上昂贵.
科学领域:
- 计算化学
- 有机电子
- 量子力学
背景情况:
- 电荷转移 (CT) 状态在有机电子学中至关重要,但其理论描述是困难的.
- 对于设计高效的发射器来说,单电位和三电位之间的精确的电位能量差距 (ΔEST) 是至关重要的.
- STGABS27基准为热激活延迟光 (TADF) 发射器提供实验 ΔEST.
研究的目的:
- 评估相关波函数方法的性能,特别是ADC(2) 和CC2,用于计算单元-三元差距.
- 研究介电溶剂模型对这些计算的准确性的影响.
- 将这些方法的准确性和计算成本与 ΔDFT 等现有基准进行比较.
主要方法:
- 使用二次代数图形构造 (ADC) 和二次近似合集群单双 (CC2) 方法.
- 使用ADC的规范和旋转缩放 (旋转组件缩放/逆旋转缩放) 和CC2的变种.
- 纳入代国家特定的COSMO溶解模型并与PCM模型进行比较.
主要成果:
- 使用旋转尺度的ADC(2) 或CC2进行代状态特定的COSMO溶解,与实验单元-三元差距达成子kcalmol−1协议.
- 这些相关波函数方法的性能与ΔDFT/PCM具有竞争力,通过排放能量交叉检查进行了验证.
- 准确的相关波函数模型比可比的ΔDFT/PCM模型慢大约100倍.
结论:
- 旋转尺度的ADC(2) 和CC2,特别是在代状态特定的COSMO解决模型中,为TADF发射器的单元-三元差距提供了高精度.
- 这些方法虽然准确,但与基于 ΔDFT 的方法相比,具有显著的计算成本.
- 精心选择理论方法和溶解模型对于有机电子材料的可靠预测至关重要.
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