We investigate the ground state properties of singly charged chlorine (Cl⁻) and gold (Au⁻) negative ions by employing four-component relativistic many-body methods. In our approach, we attach an electron to the respective outer orbitals of chlorine (Cl) and gold (Au) atoms to determine the Dirac–Fock (DF) wave functions of the ground state configurations of Cl⁻ and Au⁻, respectively. As a result, all the single-particle orbitals see the correlation effects due to the appended electron of the negative ion. After obtaining the DF wave functions, lower-order many-body perturbation methods, random-phase approximation, and coupled-cluster (CC) theory in the single and double approximation are applied to obtain the ground state wave functions of both Cl⁻ and Au⁻ ions. Then, we adopt two different approaches to the CC theory—a perturbative approach due to the dipole operator to determine electric dipole polarizability and an electron detachment approach in the Fock-space framework to estimate ionization potential. Our calculations are compared with the available experimental and other theoretical results.

我们通过采用四分量相对论多体方法研究单电荷氯 (Cl ^- ) 和金 (Au ^- ) 负离子的基态特性。在我们的方法中，我们将一个电子附加到氯 (Cl) 和金 (Au) 原子各自的外轨道，以确定 Cl ^-和 Au ^-基态构型的狄拉克-福克 (DF) 波函数， 分别。结果，由于负离子附加电子，所有单粒子轨道都看到相关效应。获得DF波函数后，应用低阶多体微扰方法、随机相位近似和单、双近似中的耦合簇（CC）理论来获得Cl ^-和Au的基态波函数^-离子。然后，我们对 CC 理论采用两种不同的方法 - 由于偶极算子确定电偶极极化率的微扰方法和 Fock 空间框架中的电子脱离方法来估计电离电位。我们的计算与可用的实验和其他理论结果进行了比较。