In this study, we have calculated single-electron energy spectra via the Green’s function based on the coupled-cluster singles and doubles (GFCCSD) method for isolated atoms from H to Ne. In order to check the accuracy of the GFCCSD method, we compared the results with the exact ones calculated from the full-configuration interaction. Consequently, we have found that the GFCCSD method reproduces not only the correct quasiparticle peaks but also satellite ones by comparing the exact spectra with the 6-31G basis set. It is also found that open-shell atoms such as C atom exhibit Mott gaps at the Fermi level, which the exact density-functional theory fails to describe. The GFCCSD successfully reproduces the Mott highest-occupied molecular orbital and lowest-unoccupied molecular orbital gaps even quantitatively. We also discussed the origin of satellite peaks as shake-up effects by checking the components of wave function of the satellite peaks. The GFCCSD is a novel cutting edge to investigate the electronic states in detail.

中文翻译：

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耦合簇单双峰（CCSD）中孤立原子的准粒子能谱：与精确CI计算的比较

在这项研究中，我们已经通过格林函数基于从H到Ne的孤立原子的耦合簇单双加法（GFCCSD）方法，计算了单电子能谱。为了检查GFCCSD方法的准确性，我们将结果与从全配置相互作用计算出的精确结果进行了比较。因此，我们发现GFCCSD方法通过将精确的光谱与6-31G基集进行比较，不仅可以再现正确的准粒子峰，而且还可以再现卫星的峰。还发现诸如C原子之类的开壳原子在费米能级上存在Mott间隙，而精确的密度泛函理论未能对此进行描述。GFCCSD成功地定量再现了Mott最高占据的分子轨道间隙和最低未占据的分子轨道间隙。我们还通过检查卫星峰值的波函数成分，讨论了作为抖动效应的卫星峰值的起源。GFCCSD是一种新颖的前沿技术，可以详细研究电子状态。