二阶Rayleigh-Schrödinger微扰理论用于Grasp
Second-Order Rayleigh-Schrödinger Perturbation Theory for the Grasp
- Institute of Theoretical Physics and Astronomy, Faculty of Physics, Vilnius University（维尔纽斯大学物理学院理论物理与天体物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文提出基于二阶Rayleigh-Schrödinger多体微扰理论的不可约张量方法，用于计算原子芯-价、芯-芯等关联，给出费曼图规则并扩展Grasp2018，以Ar II为例展示能级和跃迁计算。
中文摘要 AI 辅助
一种基于不可约张量形式的稳态二阶Rayleigh-Schrödinger多体微扰理论的方法，使我们能够确定任意具有任意数量的价电子和芯电子的原子或离子的最重要的芯-价、芯、芯-芯和价-价关联。本文介绍了描述这些关联的费曼图。此外，它还提供了从二阶多体微扰理论中得到的任何费曼图以不可约张量形式获得代数表达式的规则。虽然某些类型的价-价和芯-价关联由三粒子费曼图描述，但为了计算这些图的自旋-角部分，已对Grasp2018的程序库librang进行了额外的开发。作为所开发方法的应用示例，给出了Ar II的能级结构和跃迁数据的原子计算。
英文摘要
A developed method, based on the stationary second-order Rayleigh-Schrödinger many-body perturbation theory in an irreducible tensorial form, allows us to determine the most important core-valence, core, core-core, and valence-valence correlations for any atom or ion with an arbitrary number of valence and core electrons. This paper presents the Feynman diagrams that describe these correlations. Additionally, it provides the rules for obtaining algebraic expressions in an irreducible tensorial form for any Feynman diagram coming from second-order many-body perturbation theory. Whereas some types of the valence-valence and core-valence correlations are described by the three-particle Feynman diagrams, additional developments to calculate the spin-angular parts of these diagrams have been made to the program library librang of the Grasp2018. As an example of the application of the developed method, the atomic calculations of the energy level structure and transition data for Ar II are presented.
