最佳调节的距离隔离混合功能是否需要对分散校正进行重组? 这取决于它
Marvin Friede1, Sebastian Ehlert2, Stefan Grimme1
1Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115 Bonn, Germany.
Journal of chemical theory and computation
|November 13, 2023
概括
我们研究了区间分离混合函数 (RSH) 中的分散校正参数如何取决于区间分离参数 (ω) 的调整. 结果显示,基于PBE的RSH是强大的,而基于B88的RSH对 ω调敏感.
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:
- 与分散校正相结合的范围分离混合函数 (RSH) 是分子研究的最新技术.
- 范围分离参数 (ω) 的最佳调整可以提高激发状态的准确性,但可能会影响分散参数化.
研究的目的:
- 为了研究分散校正参数与RSH中的范围分离参数 (ω) 之间的相互依赖性.
- 评估分散模型在不同RSH的不同 ω值上的稳定性.
主要方法:
- 为六个已建立的RSH重新调整了DFT-D4分散模型.
- 探索了广泛的 ω 值 (0.050.45 a-1).
- 使用一组非共价结合的分子复合体进行参数化和测试.
主要成果:
- 基于 PBE 的 RSH 和 ωB97M-D4 在 ω 值之间显示出弱的相互依赖性和强大的性能.
- 基于B88的RSH,特别是LC-BLYP,对 ω.表现出强烈的敏感性.
- 基于B88的RSH中 ω的减少导致了系统的过度结合和性能降低.
结论:
- 选择RSH显著影响分散校正的稳定性与 ω调.
- 需要策略来缓解某些RSH的敏感性问题,以便进行精确的分子模拟.
- 未来的工作应该集中在改进的D4参数化和优化算法上.
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