# Lande g-factor values

1. Nov 13, 2006

### neu

Im getting very confused about how to calculate the lande g-factor for the 3S1, 3P0, 3P1, and 3P2 states

I know its equal to

http://www.pha.jhu.edu/~rt19/hydro/img208.gif [Broken]

but if i have state 3P0 where S=1 as 2S+1 = 3 and L=P=1 and J=0, but J=L+S which isn't =1?

i've read myself into a hole can someone help us out?

I should say the g-value is used in the zeeman effect. Gives the energy shift as ratio of bohr magneton

http://www.pha.jhu.edu/~rt19/hydro/img207.gif [Broken]

Last edited by a moderator: May 2, 2017
2. Nov 13, 2006

### OlderDan

J = L±S yes?

Last edited by a moderator: May 2, 2017
3. Nov 13, 2006

### Max Eilerson

Why would you need to calculate it if there is no electron at that energy level? Guess I'm missing something.

4. Nov 13, 2006

### nrqed

Just plug in the values of S,L and J.

Your problem does not seem to be in finding g but in vector addition in QM. Recall that in QM, writing ${\vec J } = {\vec L } + {\vec S}$ means that J will range from |L-S| to |L+S| in steps of 1. So, if S=1 and L=1, J could take any value between |1-1| and |1+1| so J may be equal to 0, 1 or 2. Your 3P0, 3P1 and 3P2 states correspond to those three possible values of J.

Hope this makes helps.

Patrick

Last edited by a moderator: May 2, 2017
5. Nov 14, 2006

### neu

Thats exactly the clarity i needed thankyou

6. Mar 10, 2011

### Shakthi

I'm stuck with calculating g and p for Eu(3+).

The outtermost orbitals in Eu is 4f7 5s2 5p6 6s2. Eu(3+) has 4f6 as the last orbital.

Thus, S = 3, L = 3 and J = 0 since J = L - S here.

How do I calculate g (using the formula given above) and then p. (p = g[S(S+1)]).

The experimental value for p = 3.4 and I read that g must be 2 in this case.

I am at a loss how to arrive at this result.

Can anyone help?

7. Mar 12, 2011

:uhh: