Fine structure of spectral lines

[Amith2006]

While going through some concepts in spectroscopy, i got stuck in fine structure lines. So, i need some clarifications in this topic. Now, it is known fact that fine structure lines can be explained by the concept of electron spin. Aren't these lines as a result of spin orbit interaction? Apart from spin orbit interaction, relativistic effects also play apart in the production of these fine lines, isn't it?

 

[jambaugh]

Yes. The magnetic interaction between the spin and the orbital rotation is different if the spin-orbit is parallel vs. anti-parallel. Thus the energy of the two cases differ slightly and you'll see two very close spectral lines for transitions into that orbital.

And yes there are relativistic corrections since near the ground state the electron's orbital velocity in so far as it is meaningful in the quantum setting is quite high.

 

[Amith2006]

That was really helpful.Thanx mate.