I was wrong, the g-factr for:
1)the lowest level in the 2D multiplet of the free La atom is 0.8 (S=1/2, L=2, J=3/2),
2)the highest level in the 2D multiplet of the free La atom is 1.2 (S=1/2, L=2, J=5/2),
3)the ground state of the la atom when it is inside lanthanum metal is 0.8, because is the same as in 1.