Precision calculations of atoms with few valence electrons

M G Kozlov

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Precision calculations of atoms with few valence electrons

M G Kozlov

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Abstract

We discuss the possibility of using pair-equations for the construction of the effective Hamiltonian $H_{\rm eff}$ for valence electrons of an atom. The low-energy part of atomic spectrum is found by solving the eigenvalue problem for $H_{\rm eff}$. In this way it is possible to account efficiently for the valence-valence and core-valence correlations. We tested this method on a toy model of a four-electron atom with the core $1s^2$. The spectrum obtained with $H_{\rm eff}$ for two valence electrons is in a perfect agreement with the full configuration interaction for all four electrons.

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M G Kozlov. 2003-06-07. Precision calculations of atoms with few valence electrons. https://arxiv.org/abs/physics/0306061

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