Table 12. Observed energy levels of the 4p⁴(³P₂)nd ⁴F_9/2 series compared with calculations using the Ritz formula, as described in the text.

All energies are stated in kaysers.

α=1.35276

β= −3.442×10⁻⁶

Config.	Observed	Calculated	Obs.-calc.
4d	80587.61	80221.57	+ 366.04
5d	87191.97	87160.44	+ 31.53
6d	90244.89	90241.40	+ 3.49
7d	91851.14	91858.17	−7.03
4p4(1D2)4d 2G9/2 = 91921.86
8d	92807.81	92807.63	+ 0.18
9d	93411.48	93411.49	−0.01
10d	93818.96	93818.95	+ 0.01
11d	94106.70	94106.70	0.00
12d	94317.40	94317.40	0.00