* ¹ (multiplicity): This superscript indicates the spin multiplicity, which is calculated as 2S+1, where S is the total spin angular momentum of the atom. In this case, the multiplicity is 1, meaning S = 0. This tells us that the atom has no net spin angular momentum.
* D (orbital angular momentum): This letter represents the total orbital angular momentum (L) of the atom. Each letter corresponds to a specific value of L:
* S: L = 0
* P: L = 1
* D: L = 2
* F: L = 3
* and so on...
Therefore, ¹D₂ indicates that the atom has a total orbital angular momentum of L = 2.
* ₂ (total angular momentum): This subscript represents the total angular momentum (J) of the atom. J is the vector sum of L and S: J = L + S. Since S = 0 in this case, J = L = 2.
In summary, the term symbol ¹D₂ indicates that the atom has no net spin angular momentum (S = 0), a total orbital angular momentum of L = 2, and a total angular momentum of J = 2.
