G-factor of Co 2+

jameson2

1. The problem statement, all variables and given/known data
Why is the g-factor found to be >2 for Co 2+ ions when they are ascribed a spin only moment?


2. Relevant equations



3. The attempt at a solution
The expression for the g-factor gives 2 for spin only. The only thing I can think of is that the g-factor is actually 2.0023, rather than 2, but this doesn't seem right as the question refers to this particular ion rather than electrons in general.