# Spectroscopic/term symbol atomic physics question

1. May 16, 2008

### bman!!

Sodium, = 11, has the ground state configuration [Ne] 3s^1 and is a “one
electron” atom. Magnesium, Z= 12, is a “two-electron” atom. Write down its
ground state configuration and possible term values.

i think i get the right answer but im having a couple of issues:

ground state configuration: [Ne] 3s^2

possible term values are for the spin multiplicity either S = 1 or 0 so 2S+1 = 3 or 1

L = 0 therefore = 0

therefore J = 1 or 3

however im inclined to go with J = 1 as i think the exclusion plays a role.

p.s. ill happily clarify anything here as i know its not the clearest, i just dont know how to wrie term/spectroscopic notation in latex/html

cheers

i just find this term symbol stuff abit cinfusing

2. May 17, 2008

### malawi_glenn

No, your J - value is wrong.

Tell me, what is the formula for adding two angular momentums in quantum mechanics. i.e What is the formula for J in this case?

This is the way to write a Term:

$$^{2S+1}L_J$$

Just click on this image to see the Tex-code, you should figure out how to chage the code to fit your needs-

Also, this is wrong:

"ground state configuration: [Ne] 3s^2"
We were discussing Mg right?

3. May 22, 2008

### bman!!

its ok i spoke to a chemist and he set me straight. besides, ive already had that exam, so i can set about forgetting everything i learnt ;)