结合集群激发能量的加速基数汇聚,使用基于密度的基数校正方法
Diata Traore1, Julien Toulouse1,2, Emmanuel Giner1
1Laboratoire de Chimie Théorique, Sorbonne Université and CNRS, UMR 7616, F-75005 Paris, France. emmanuel.giner@lct.jussieu.fr.
Faraday discussions
|July 30, 2024
概括
我们开发了一种计算上便宜的方法来改善电子激发能量的基础集收. 这种方法可以加速使用分子系统的运动方程合集群单双 (EOM-CCSD) 的计算.
科学领域:
- 计算化学的计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 基本集的融合对于准确的量子化学计算至关重要.
- 运动方程合集群单双 (EOM-CCSD) 是计算激发能量的广泛使用的方法.
- 标准EOM-CCSD可能会受到基准集的缓慢融合的影响,需要昂贵的大型基准集.
研究的目的:
- 将新的线性响应理论用于基于密度的基数组校正,应用于真实分子系统.
- 为了加快以EOM-CCSD方法计算的激发能量的基础集收.
- 评估拟议的计算价格低廉的基础集合校正方法的效率和准确性.
主要方法:
- 应用线性响应理论用于基于密度的基数组校正.
- 使用近似的线性响应框架,忽略密度函数的二次导数.
- 在Hartree-Fock密度下评估基数校正潜力.
主要成果:
- 该方法在5个小分子系统的约30个激发能量上进行了测试.
- 对Rydberg状态的激发能被确定为基础设置错误的主要来源.
- 经基数组校正的EOM-CCSD方法在aug-cc-pVTZ基数组中实现了0.02 eV的平均绝对偏差,而标准EOM-CCSD的0.04 eV.
结论:
- 开发的方法提供了一种计算成本低廉的方法,可以加速激发能量的基础集收.
- 这种方法显示出作为一种替代明确相关的方法来提高EOM-CCSD准确性的方法.
- 这项工作为更有效,更准确的分子激发能量的理论预测铺平了道路.
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