Electronic structure of silicon Rydberg series. I. The (3pnd))Do1,Do3,Fo1, andFo3series

Abstract

The ($3{s}^{2}3pnd$) $^{1}D^{o}$, $^{3}D^{o}$, $^{1}F^{o}$, and $^{3}F^{o}$ Rydberg series of the silicon atom are investigated by a restricted Hartree-Fock calculation and configuration interaction (CI) calculations of various levels. The relative energies with respect to the ionized level $(3{s}^{2}3p)^{2}P^{o}$ given by the largest CI calculation in the present work are -2.63, -1.46, -0.85, -0.55, -0.38, and -0.28 eV, respectively, for the first six members of the $^{3}D^{o}$ series, while the experimental values are -2.56, -1.45, -0.85, -0.55, -0.38, and -0.27 eV. The agreement between the two is excellent. The configuration $(3s3{p}^{3})^{3}D^{o}$ is predominant in the first member of the $^{3}D^{o}$ series, and it also acts as a strong series perturber in the rest of the series. For the $^{1}D^{o}$ series the relative energies with respect to $^{2}P^{o}$ by the largest CI calculation are -2.27, -1.16, -0.70, -0.46, and -0.32 eV, respectively, whereas the experimental values are -2.31, -1.17, -0.70, -0.47, and -0.34 eV. In this series, $(3s3{p}^{3})^{1}D^{o}$ acts as a series perturber just as $3s3{p}^{3}$ does in the $^{3}D^{o}$ series. At any levels of the approximations, $(3s3{p}^{3})^{1}D^{o}$ is not found below the $^{2}P^{o}$ state. The ($3{s}^{2}3pnd$) $^{1}F^{o}$ and $^{3}F^{o}$ series are found to be pure Rydberg series.