Does spin orbit coupling cause the split in the energy level of the electron?

[Edge5]

Hi,

As far as I understand spin orbit coupling is the interaction between proton of atom and electron. Proton's motion(from the frame of electron) around electron creates magnetic field. Hence electron experiences magnetic field. Does this magnetic field produces a Zeeman effect which cause split in the energy levels?Or does it only cause a shift? Or both ? :)

 

[king vitamin]

Yes, this both shifts and splits the energy levels of the electron. However, since total angular momentum $\vec{L} + \vec{S}$ is still conserved by the spin-orbit interaction, it will not completely split the degeneracies in the spectrum. This should be treated by any good undergraduate quantum mechanics textbook.