在国家平均驱动的相似性重规范化组中,对旋转轨道合的成本效益治疗第二阶段扰乱理论
1Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
Molecules (Basel, Switzerland)
|May 14, 2025
概括
我们开发了一种经济的方法来计算量子化学中的自旋轨道合 (SOC) 效应. 这种新方法,BP1-SA-DSRG-PT2c,为原子和分子提供精确的能量光谱,并具有高效的计算缩放.
科学领域:
- 量子化学 是一个量子化学.
- 计算物理 计算物理
- 电子结构理论 电子结构理论
背景情况:
- 旋转轨道合 (SOC) 对于准确描述电子结构至关重要,特别是重元素.
- 现有的SOC处理方法可能在计算上昂贵,限制了它们的应用.
- 国家平均驱动的相似性重规范化组二次扰动理论 (SA-DSRG-PT2) 是电子相关性的强大工具,但需要有效的SOC整合.
研究的目的:
- 在SA-DSRG-PT2框架内开发一种经济且准确的方法来处理旋转轨道合 (SOC).
- 为了降低与计算电子结构计算中的SOC效应相关的计算成本.
- 评估新方法在各种原子和分子系统上的性能.
主要方法:
- 通过SA-DSRG-PT2的无旋转汉密尔顿数引入了电子相关性.
- 用布雷特-保利哈密尔顿式增强了哈密尔顿式,并使用自旋纯度参考状态对角化.
- 采用旋转轨道平均场近似来降低两电子SOC积分的成本.
- 开发了BP1-SA-DSRG-PT2c方法,其计算缩放与其非相对论对应物相似.
主要成果:
- 在BP1-SA-DSRG-PT2c方法中,垂直过渡能量只需要一个和两个体密度的累积物.
- 对原子和分子获得了精确的SOC校正的能量光谱.
- 该方法的准确性与已建立的内部合约的多引用扰乱理论与SOC.相比,准确性相当.
结论:
- BP1-SA-DSRG-PT2c提供了一种高效准确的方法,用于将旋转轨道合纳入量子化学计算中.
- 该方法适用于研究SOC效应显著的系统,包括主要组,过渡金属和活性化物化合物.
- 这一发展提升了计算化学在准确电子结构预测方面的能力.
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