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Variational Calculations For The Lithium Isoelectronic Sequence., Mauro. Tambasco

Electronic Theses and Dissertations

Variational eigenvalues for the $1s\sp2 2s\ \sp2S$ and $1s\sp2 2p\ \sp2P$ states of the lithium isoelectronic sequence $(3 \le Z \le 15)$ are calculated using multiple basis sets in Hylleraas coordinates. A systematic convergence pattern for each of these nonrelativistic energies is established, and extrapolated values are determined to within an accuracy of several parts in 10$\sp{10}$ to 10$\sp{11}.$ An analytical calculation to determine the first two coefficients $\varepsilon\sp{(0)}$ and $\varepsilon\sp{(1)}$ of the Z-expansion for the above states of the lithium isoelectronic sequence is also presented. Using improved electron-pair energies, the third coefficient $\varepsilon\sp{(2)}$ for the above states is determined …