Methods are presented for determining singlet-triplet mixing angles from measured energy-level data in two-valence electron systems, and for utilizing these mixing angles to specify E1 and M1 oscillator strengths and magnetic g factors from LS coupling and hydrogenic formulas and from data obtained in single-valence electron systems. These methods are tested through studies of line strengths in the He, Mg, Ne, Si, and S isoelectronic sequences and of g factors in the Kr and Pb atoms.

• Received 24 July 1989

DOI:https://doi.org/10.1103/PhysRevA.40.6958