Reference,
https://en.wikipedia.org/wiki/Term_symbol
James E. Huheey, Ellen A. Keiter, Richard L.Keiter and Okhil K. Medhi, Inorganic Chemistry, Principles of Structure and Reactivity. 4th Edn. Pearsons
EPANDING THE CONTENT OF AN OUTLINE using notes.pptx
Term symbols
1. Spectroscopic
Term symbols
Mr. Mithil Fal Desai, Ph. D.
Assistant Professor in Chemistry
Shree Mallikarjun and Shri Chetan Manju
Desai College
Canacona, Goa
2. 2
The term symbols are a symbolic representation of energy,
angular momentum and spin multiplicity of an atom.
For a Hydrogen atom it is defined as S, P, D, F states,
depending upon the electron occupancy in s, p, d and f
orbitals.
Term Symbol
3. L 0 1 2 3
Ground term S P D F
Components in
octahedral field
A1g T1g T2g, Eg A2g, T1g, T2g
Splitting of dn terms in an octahedral field
3
4. No. of d
electrons
l
Orbital
momentu
m
Term Total spin (S)
Free
ion
ground
state
Ground
term in
octahedral
field
Excited state
term with
same spin
multiplicity
2 1 0 -1 -2 Σl=L Σs=S 2S+1 2S+1L
1 ↑ - - - - 2 D 1/2*1 2 2D 2T2g
2Eg
2 ↑ ↑ - - - 3 F 1/2*2 3 3F 3T1g
3T2g,3A2g, 3T1g(P)
3 ↑ ↑ ↑ - - 3 F 1/2*3 4 4F 4A2g
4T2g,4T1g, 4T1g(P)
4 ↑ ↑ ↑ ↑ - 2 D 1/2*4 5 5D 5Eg
5T2g
5 ↑ ↑ ↑ ↑ ↑ 0 S 1/2*5 6 6S 6A1g None
6 ↑↓ ↑ ↑ ↑ ↑ 2 D 1/2*4 5 5D 5T2g
5Eg
7 ↑↓ ↑↓ ↑ ↑ ↑ 3 F 1/2*3 4 4F 4T1g
4T2g,4A2g, 4T1g(P)
8 ↑↓ ↑↓ ↑↓ ↑ ↑ 3 F 1/2*2 3 3F 3A2g
3T2g,3T1g, 3T1g(P)
9 ↑↓ ↑↓ ↑↓ ↑↓ ↑ 2 D 1/2*1 2 2D 2Eg
2T2g
Determination of term symbols
4