| Index | Configuration | Level | Expt.a | CHIANTIb | GRASPc | GRASPd |
| 1 | 1s2 | 1S0 | 0.00000 | 0.000000 | 0.00000 | 0.00000 |
| 2 | 1s2s | 3S1 | 228.15015 | 228.225601 | 228.20039 | 227.97345 |
| 3 | 1s2p | 3P0 |
229.52797 | 229.586395 | 229.55811 | 229.37311 |
| 4 | 1s2p | 3P1 |
229.57456 | 229.683594 | 229.64185 | 229.41945 |
| 5 | 1s2s | 1S0 | 229.64803 | 229.813187 | 229.79482 | 229.59423 |
| 6 | 1s2p | 3P2 |
229.77757 | 229.942795 | 229.85488 | 229.61924 |
| 7 | 1s2p | 1P1 |
230.75280 | 231.076797 | 230.91628 | 230.67177 |
| 8 | 1s3s | 3S1 | 270.03877 | 270.118805 | 270.10078 | 269.86520 |
| 9 | 1s3p | 3P0 |
270.41842 | 270.507599 | 270.48924 | 270.26436 |
| 10 | 1s3p | 3P1 |
270.43266 | 270.539978 | 270.51412 | 270.27814 |
| 11 | 1s3s | 1S0 | 270.43505 | 270.539978 | 270.56681 | 270.33115 |
| 12 | 1s3p | 3P2 |
270.49291 | 270.604797 | 270.57739 | 270.33735 |
| 13 | 1s3d | 3D1 | 270.70342 | 270.831604 | 270.76091 | 270.52312 |
| 14 | 1s3d | 3D2 | 270.70332 | 270.831604 | 270.76537 | 270.52336 |
| 15 | 1s3d | 3D3 | 270.72730 | 270.864014 | 270.78817 | 270.54629 |
| 16 | 1s3d | 1D2 | 270.73840 | 270.896393 | 270.79950 | 270.55973 |
| 17 | 1s3p | 1P1 |
270.75700 | 270.896393 | 270.90193 | 270.65251 |
| 18 | 1s4s | 3S1 | 284.49700 | 284.569214 | 284.51374 | 284.33206 |
| 19 | 1s4p | 3P0 |
284.65550 | 284.731201 | 284.66948 | 284.51012 |
| 20 | 1s4p | 3P1 |
284.66200 | 284.731201 | 284.67979 | 284.51602 |
| 21 | 1s4s | 1S0 | 284.66300 | 284.731201 | 284.70448 | 284.54750 |
| 22 | 1s4p | 3P2 |
284.68700 | 284.763611 | 284.76417 | 284.54187 |
| 23 | 1s4f | 3F2 |
284.893188 | 284.78987 | 284.59841 | |
| 24 | 1s4f | 3F3 |
284.893188 | 284.79216 | 284.59761 | |
| 25 | 1s4f | 3F4 |
284.893188 | 284.79899 | 284.60335 | |
| 26 | 1s4f | 1F3 |
284.893188 | 284.80109 | 284.60404 | |
| 27 | 1s4d | 3D1 | 284.77650 | 284.860771 | 284.80115 | 284.61206 |
| 28 | 1s4d | 3D2 | 284.77600 | 284.860771 | 284.80523 | 284.61259 |
| 29 | 1s4d | 3D3 | 284.78659 | 284.893188 | 284.80532 | 284.62291 |
| 30 | 1s4d | 1D2 | 284.79100 | 284.893188 | 284.80839 | 284.63107 |
| 31 | 1s4p | 1P1 |
284.79900 | 284.893188 | 284.89237 | 284.69334 |
| 32 | 1s5s | 3S1 | 291.14600 | 291.211212 | 291.25271 | 290.94261 |
| 33 | 1s5p | 3P0 |
291.22781 | 291.276001 | 291.30708 | 291.02186 |
| 34 | 1s5p | 3P1 |
291.23100 | 291.308411 | 291.32863 | 291.02504 |
| 35 | 1s5s | 1S0 | 291.23200 | 291.308411 | 291.32863 | 291.02873 |
| 36 | 1s5p | 3P2 |
291.24393 | 291.308411 | 291.33041 | 291.03802 |
| 37 | 1s5d | 3D1 | 291.373199 | 291.33041 | 291.08109 | |
| 38 | 1s5d | 3D2 | 291.373199 | 291.35444 | 291.08138 | |
| 39 | 1s5d | 3D3 | 291.373199 | 291.35978 | 291.08625 | |
| 40 | 1s5f | 3F2 |
291.373199 | 291.37420 | 291.08943 | |
| 41 | 1s5f | 3F3 |
291.373199 | 291.37423 | 291.08909 | |
| 42 | 1s5d | 1D2 | 291.29700 | 291.373199 | 291.37860 | 291.08971 |
| 43 | 1s5f | 3F4 |
291.373199 | 291.37947 | 291.09206 | |
| 44 | 1s5f | 1F3 |
291.373199 | 291.37950 | 291.09237 | |
| 45 | 1s5g | 3G3 | 291.373199 | 291.40201 | 291.09235 | |
| 46 | 1s5g | 3G4 | 291.373199 | 291.40291 | 291.09214 | |
| 47 | 1s5g | 3G5 | 291.373199 | 291.40919 | 291.09395 | |
| 48 | 1s5g | 1G4 | 291.373199 | 291.41330 | 291.09409 | |
| 49 | 1s5p | 1P1 |
291.30100 | 291.373199 | 291.41497 | 291.09523 |
|
a NIST (http://physics.nist/gov/PhysRefData). b Energy levels of Sampson et al. (1983) from CHIANTI database (http://wwwsolar.nrl.navy.mil/chianti.html). c Present results from GRASP without Breit and QED effects. d Present results from GRASP with Breit and QED effects. |