基于冷的自然旋转子的低成本相对论运动方程合集群方法:一个国家特定的方法
Tamoghna Mukhopadhyay1, Mrinal Thapa1, Somesh Chamoli1
1Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
The Journal of chemical physics
|November 18, 2025
概括
我们开发了一种具有成本效益的相对论运动方程合集群单双 (EOM-CCSD) 方法,使用州特定的冷自然旋转器 (SS-FNS). 这种方法显著改善了激发状态计算,并降低了大规模研究的计算成本.
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:
- 相对论效应对于准确计算重元素的电子结构至关重要.
- 运动方程合集群单双 (EOM-CCSD) 是一种强大的激发状态属性的方法.
- 开发用于相对论激发状态计算的计算效率高的方法仍然是一个挑战.
研究的目的:
- 提出一个低成本的相对论EOM-CCSD方法,使用国家特定的冷自然旋转器 (SS-FNSs).
- 实施和基准测试这种方法来计算激发能和过渡性质.
- 在这个框架内评估精确的二元原子平均场 (X2CAMF) 哈密尔顿式的性能.
主要方法:
- 开发SS-FNS的理论框架,该框架来自第二阶代数图形构造方法.
- 使用四组分迪拉克-库伦和X2CAMF哈密尔顿的相对论SS-FNS-EE-EOM-CCSD方法的实施.
- 与标准相对论EOM-CCSD方法进行比较,使用未截断的旋转基.
主要成果:
- 与基于MP2的FNS相比,SS-FNS-EE-EOM-CCSD方法显示了顺的融合,并提高了激发能量的精度.
- 基于X2CAMF的相对论EOM-CCSD方法提供了与标准方法非常一致的结果.
- 这样可以大大降低计算成本,使大规模计算成为可能.
结论:
- 开发的SS-FNS-EE-EOM-CCSD方法为相对论激发状态计算提供了一个计算效率高,准确的方法.
- 基于X2CAMF的相对论EOM-CCSD方法是大规模量子化学应用的一个有前途的工具.
- 这项工作为在相对论系统中电子激发状态的更容易和更有效的理论研究铺平了道路.
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