ENERGY AND FINE-STRUCTURE OF 1S(2)ND AND 1S(2)NF STATES FOR THE LITHIUM ISOELECTRONIC SEQUENCE

The non-relativistic energies of 1s2 nd (n = 3, 4 and 5) and 1s2 nf (n = 4 and 5) states for the lithium isoelectronic sequence from Li I to Ne VIII are calculated with a full-core plus correlation method using multiconfiguration interaction wavefunctions. Relativistic and mass-polarization effects on the energy are evaluated perturbatively as the first-order corrections. The fine structure is calculated by using spin-orbit and spin-other-orbit interaction operators. Our results are in excellent agreement with experimental data in the literature. Possible misidentifications in the observed optical spectra are pointed out. They show that this full-core plus correlation method is useful for excited atomic systems with a 1s2 core.