Details: Each level is characterized by the value of the usual quantum numbers
J and K = Ka, and by an overall torsion-wagging-rotation symmetry species Γ corresponding to
an irreducible representation of the permutation-inversion group G12. To distinguish between two doubly degenerate levels
of E1 or E2 symmetry with the same J, K, the notation
E1+1 and E1-1, or E2+1 and E2-1 is used, where +1 and -1 levels correspond to k=K>0 and k=-K<0
respectively. When table includes hyperfine levels, standard F = J+I quantum number is added to the labeling.
The correspondence between integer Sym number in .cat file and symmetry species Γ is
given in the table →
| Sym | Γ |
|---|---|
| 3 | A1 |
| -3 | A2 |
| 4 | B1 |
| -4 | B2 |
| 1 | E1+1 |
| -1 | E1-1 |
| 2 | E2+1 |
| -2 | E2-1 |
Details: Each level is characterized by the usual asymmetric top quantum numbers
J, Ka, and Kc, and the free rotor quantum number m.
When table includes hyperfine levels, standard F = J+I quantum number is added to the labeling.
The correspondence between
m quantum number in .cat file and the vibrational torsional quantum number vt and symmetry species Γ = A or E
of C3v symmetry point group is given in the table →
| m | vt | Γ |
|---|---|---|
| 0 | 0 | A |
| 1 | 0 | E |
| -3 | 1 | A |
| -2 | 1 | E |
| 3 | 2 | A |
| 4 | 2 | E |
| -6 | 3 | A |
| -5 | 3 | E |
| 6 | 4 | A |
| 7 | 4 | E |
Details: Each level is characterized by the usual asymmetric top quantum numbers J, Ka, and Kc, and symmetry number σ. A combination of (σ1,σ2) values of upper and lower levels corresponds to a combination of symmetry species Γ1Γ2 of C3v symmetry point group. The correspondence is given in the table →
| (σ1,σ2) | Γ1Γ2 |
|---|---|
| (0,0) | AA |
| (0,1) | AE |
| (1,0) | EA |
| (1,1) | EE |
| (1,2) | EE' |
Lille Spectroscopic Database