Atomic energy levels and Landé g factors: A theoretical study.

We have developed a relativistic multichannel theory that can be used to calculate the multichannel quantum-defect theory parameters (mu(alpha), U-i alpha) directly from first principles. With the parameters we can calculate the energy levels and Lande g factors of Rydberg series based on the multichannel quantum-defect theory. We have performed calculations of excited states for the Ne atom with major configuration 1s(2)2s(2)2p(5)np in J(pi) = 0(+), 1(+), 2(+), and 3(+) symmetry. The results are in good agreement with the experimental data. We have also found that the coupling scheme is dependent on the total angular momentum J. The jl-coupling scheme is more suitable than the jj-coupling scheme in describing J(pi) = 1(+) symmetry, whereas the jj-coupling scheme is more suitable than the jl-coupling scheme for J(pi) = 2(+) symmetry.