How to calculate ground state term symbol?
Answers
Answered by
0
As an example, in the case of fluorine, the electronic configuration is 1s22s22p5.
1. Discard the full subshells and keep the 2p5 part. So there are five electrons to place in subshell p (l = 1).
2. There are three orbitals (ml = 1, 0, −1) that can hold up to 2(2l + 1) = 6 electrons. The first three electrons can take ms = ½ (↑) but the Pauli exclusion principle forces the next two to have ms = −½ (↓) because they go to already occupied orbitals.
ml
+1 0 −1
ms: ↑↓ ↑↓ ↑
3. S = ½ + ½ + ½ − ½ − ½ = ½; and L = 1 + 0 − 1 + 1 + 0 = 1, which is "P" in spectroscopic notation.
4. As fluorine 2p subshell is more than half filled, J = L + S = 3⁄2. Its ground state term symbol is then 2S+1LJ = 2P3⁄2.
1. Discard the full subshells and keep the 2p5 part. So there are five electrons to place in subshell p (l = 1).
2. There are three orbitals (ml = 1, 0, −1) that can hold up to 2(2l + 1) = 6 electrons. The first three electrons can take ms = ½ (↑) but the Pauli exclusion principle forces the next two to have ms = −½ (↓) because they go to already occupied orbitals.
ml
+1 0 −1
ms: ↑↓ ↑↓ ↑
3. S = ½ + ½ + ½ − ½ − ½ = ½; and L = 1 + 0 − 1 + 1 + 0 = 1, which is "P" in spectroscopic notation.
4. As fluorine 2p subshell is more than half filled, J = L + S = 3⁄2. Its ground state term symbol is then 2S+1LJ = 2P3⁄2.
Similar questions