orbitals using coupled-cluster singles and doubles (CCSD) and self-energy functional theory*

We examine the electronic correlation effects of isolated atoms containing d orbitals by using calculations based on the CCSD and the self-energy functional theories. The self-energy functional theory[1] was proposed originally for analyzing models of correlated systems. We adopt it for realistic description of the atoms by employing exact diagonalization of their second-quantized Hamiltonians. We calculate the single-particle Green's functions[2] to clarify how the many-body nature of the atoms affects on the spectral functions. We also discuss the differences in the spectra between both methods.

[1] M. Potthoff, Eur. Phys. J. B 36, 335 (2003); M. Potthoff, M. Aichhorn, and C. Dahnken, Phys. Rev. Lett. 91, 206402 (2003);
[2] K. Bhaskaran-Nair, K. Kowalski, and W. A. Shelton, J. Chem. Phys. 144, 144101 (2016) and references therein.