Actinium Ac II
Odd levels
Even levels
7s7p
3
P
0
20 956
6d7p
3
F
2
28 201
5f7s
1
F
3
29 881*
5f6d
3
H
4
39 807
7s
2
1
S
0
0
6d7s
3
D
1
4 740
6d
2
3
F
2
13 236
7p
2
3
P
0
49 000 ± 3 000
7s8s
3
S
l
51 681
5f7p
3
F
2
54 633
5f
2
3
H
4
69 000 ± 5 000
Ionization limit
: 95 000 ± 1 500 cm
-1
(2)
S.E.
* perturbed level
(2)
: J.F. Wyart, unpublished