It was first observed by its namesake in the D lines of sodium and its anomalous variety occurs when electron spin contributes to this phenomenon.
Mössbauer spectroscopy involves the observation of phenomena including isomer shifts and this.  An equation describing it contains an electron spin g-factor of approximately two. It was first observed by its namesake in the D lines of sodium and its anomalous variety occurs when electron spin contributes to this phenomenon. A potential energy associated with it is proportional to the Bohr magneton, the Lande g-factor, and the z component of the total momentum. This is the magnetic analog to the Stark effect, and in strong fields it becomes the Paschen-Back effect. The inverse type of it considers absorption lines as opposed to spectral lines. For 10 points, name this splitting of spectral lines in a magnetic field.
Mössbauer spectroscopy involves the observation of phenomena including isomer shifts and this.  
{Zeeman} Effect