ABSTRACT
There are many kinds of effects that resolve the degeneracy in many atomic systems, including external electric and magnetic fields that tend to orient particles or states with electric or magnetic dipole moments, and a number of internal interactions between the particles themselves, either due to their spin or their dipole moments. The agreement between the calculated splittings based on quantum mechanical perturbation calculations and the measured splittings measured in atomic spectroscopy is one of the most impressive accomplishments of quantum mechanics. For the effects of spin-spin correlations, we will examine the phenomenon only qualitatively, but for spinorbit effects and external magnetic field effects, we will examine the effects quantitatively.
