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| NIST Atomic Spectra Database Ionization Energies Data
Fr (all spectra) |
Example of how to reference these results:
Kramida, A., Ralchenko, Yu., Reader, J., and NIST ASD Team (2024). NIST Atomic Spectra Database (ver. 5.12), [Online]. Available: https://physics.nist.gov/asd [2025, June 13]. National Institute of Standards and Technology, Gaithersburg, MD. DOI: https://doi.org/10.18434/T4W30F
BibTex Citation (new window)
|
| At. Num. | Ion Charge | El. name | Ionization Energy (eV) |
Uncertainty (eV) |
References |
|---|---|---|---|---|---|
| 87 | 0 | Francium | 4.0727411 | 0.0000011 | L10714 |
| 87 | +1 | Francium | [22.4] | 1.9 | L16139 |
| 87 | +2 | Francium | [33.5] | 1.5 | L16139 |
| 87 | +3 | Francium | (39.1) | 1.7 | L8672c99 |
| 87 | +4 | Francium | (50.0) | 1.9 | L8672c99 |
| 87 | +5 | Francium | (67.0) | 2.0 | L8672c99 |
| 87 | +6 | Francium | (80.0) | 2.0 | L8672c99 |
| 87 | +7 | Francium | (106.0) | 2.1 | L8672c99 |
| 87 | +8 | Francium | (120.0) | 2.2 | L8672c99 |
| 87 | +9 | Francium | (179.0) | 2.2 | L8672c99 |
| 87 | +10 | Francium | (200.0) | 2.4 | L8672c99 |
| 87 | +11 | Francium | (222.1) | 2.5 | L8672c99 |
| 87 | +12 | Francium | (245) | 3 | L8672c99 |
| 87 | +13 | Francium | (269) | 3 | L8672c99 |
| 87 | +14 | Francium | (293) | 3 | L8672c99 |
| 87 | +15 | Francium | (324) | 3 | L8672c99 |
| 87 | +16 | Francium | (349) | 3 | L8672c99 |
| 87 | +17 | Francium | (375) | 3 | L8672c99 |
| 87 | +18 | Francium | (400) | 3 | L8672c99 |
| 87 | +19 | Francium | (530) | 30 | L582 |
| 87 | +20 | Francium | (560) | 30 | L582 |
| 87 | +21 | Francium | (590) | 30 | L582 |
| 87 | +22 | Francium | (620) | 30 | L582 |
| 87 | +23 | Francium | (690) | 30 | L582 |
| 87 | +24 | Francium | (720) | 40 | L582 |
| 87 | +25 | Francium | (810) | 40 | L582 |
| 87 | +26 | Francium | (850) | 40 | L582 |
| 87 | +27 | Francium | (910) | 50 | L582 |
| 87 | +28 | Francium | (980) | 50 | L582 |
| 87 | +29 | Francium | (1 040) | 50 | L582 |
| 87 | +30 | Francium | (1 110) | 50 | L582 |
| 87 | +31 | Francium | (1 180) | 60 | L582 |
| 87 | +32 | Francium | (1 250) | 60 | L582 |
| 87 | +33 | Francium | (1 320) | 70 | L582 |
| 87 | +34 | Francium | (1 380) | 70 | L582 |
| 87 | +35 | Francium | (1 460) | 70 | L582 |
| 87 | +36 | Francium | (1 530) | 80 | L582 |
| 87 | +37 | Francium | (1 600) | 80 | L582 |
| 87 | +38 | Francium | (1 670) | 90 | L582 |
| 87 | +39 | Francium | (1 740) | 90 | L582 |
| 87 | +40 | Francium | (1 810) | 90 | L582 |
| 87 | +41 | Francium | (2 119) | 4 | L8672c99 |
| 87 | +42 | Francium | (2 182) | 4 | L8672c99 |
| 87 | +43 | Francium | (2 247) | 4 | L8672c99 |
| 87 | +44 | Francium | (2 317) | 4 | L8672c99 |
| 87 | +45 | Francium | (2 384) | 4 | L8672c99 |
| 87 | +46 | Francium | (2 450) | 4 | L8672c99 |
| 87 | +47 | Francium | (2 564) | 4 | L8672c99 |
| 87 | +48 | Francium | (2 631) | 4 | L8672c99 |
| 87 | +49 | Francium | (2 706) | 4 | L8672c99 |
| 87 | +50 | Francium | (2 774) | 4 | L8672c99 |
| 87 | +51 | Francium | (3 049) | 4 | L8672c99 |
| 87 | +52 | Francium | (3 115) | 4 | L8672c99 |
| 87 | +53 | Francium | (3 190) | 5 | L8672c99 |
| 87 | +54 | Francium | (3 257) | 5 | L8672c99 |
| 87 | +55 | Francium | (3 556) | 5 | L8672c99 |
| 87 | +56 | Francium | (3 635) | 5 | L8672c99 |
| 87 | +57 | Francium | (3 828) | 6 | L8672c99 |
| 87 | +58 | Francium | [3 907] | 4 | L10278 |
| 87 | +59 | Francium | (6 365) | 7 | L8672c99 |
| 87 | +60 | Francium | (6 516) | 10 | L8672c99 |
| 87 | +61 | Francium | (6 678) | 12 | L8672c99 |
| 87 | +62 | Francium | (6 849) | 15 | L8672c99 |
| 87 | +63 | Francium | (7 013) | 19 | L8672c99 |
| 87 | +64 | Francium | (7 172) | 24 | L8672c99 |
| 87 | +65 | Francium | (7 500) | 30 | L8672c99 |
| 87 | +66 | Francium | (7 670) | 40 | L8672c99 |
| 87 | +67 | Francium | (7 850) | 40 | L8672c99 |
| 87 | +68 | Francium | (8 020) | 50 | L8672c99 |
| 87 | +69 | Francium | (8 500) | 50 | L8672c99 |
| 87 | +70 | Francium | (8 640) | 60 | L8672c99 |
| 87 | +71 | Francium | (8 800) | 60 | L8672c99 |
| 87 | +72 | Francium | (8 950) | 70 | L8672c99 |
| 87 | +73 | Francium | (9 890) | 90 | L8672c99 |
| 87 | +74 | Francium | (10 070) | 90 | L8672c99 |
| 87 | +75 | Francium | (10 420) | 100 | L8672c99 |
| 87 | +76 | Francium | (10 590) | 110 | L8672c99 |
| 87 | +77 | Francium | (22 330) | 120 | L8672c99 |
| 87 | +78 | Francium | (22 730) | 120 | L8672c99 |
| 87 | +79 | Francium | (23 170) | 140 | L8672c99 |
| 87 | +80 | Francium | (23 570) | 150 | L8672c99 |
| 87 | +81 | Francium | (27 060) | 160 | L8672c99 |
| 87 | +82 | Francium | (27 590) | 170 | L8672c99 |
| 87 | +83 | Francium | (28 260) | 190 | L8672c99 |
| 87 | +84 | Francium | (28 683.4) | 0.5 | L16264c99 |
| 87 | +85 | Francium | (113 821.9) | 0.5 | L21139 |
| 87 | +86 | Francium | (115 857.5) | 0.7 | L19200 |
If you did not find the data you need, please inform the ASD Team.
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