Open Access
Table 3
Helium energy levels.
| Level | E (cm−1) | E (eV) | Designation |
|---|---|---|---|
| 0 | 0.000 | 0.000 | He I 1s2 1S0 |
| 1 | 159 852.231 | 19.819 | He I 1s 2s 3S1 |
| 2 | 166273.513 | 20.615 | He I 1s 2s 1S0 |
| 3 | 169 083.059 | 20.964 | He I 1s 2p 3Po |
| 4 | 171 131.075 | 21.218 | He I 1s 2p  |
| 5 | 198 420.575 | 24.601 | He II 1s 2S1/2 |
| 6 | 527 600.309 | 65.415 | He II 2s 2S1/2 |
| 7 | 527 603.747 | 65.415 | He II 2p 2Po |
| 8 | 637 329.434 | 79.019 | He III |
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