NIST Atomic Ionization Energies Output

NIST Physical Measurement Laboratory

NIST Atomic Spectra Database Ionization Energies Data Tm (all spectra) 69 Data Rows Found	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 [2026, October 26]. National Institute of Standards and Technology, Gaithersburg, MD. DOI: https://doi.org/10.18434/T4W30F BibTex Citation (new window)

Ionization Energy (cm^-1)
49 880.57
[97 310]
[190 830]
[342 060]
[527 700]
(789 000)
(932 000)
(1 076 000)
(1 292 000)
(1 448 000)
(1 652 000)
(1 930 000)
(2 208 000)
(2 380 000)
(2 560 000)
(2 840 000)
(3 120 000)
(3 420 000)
(3 710 000)
(4 000 000)
(4 280 000)
(4 570 000)
(4 860 000)
(6 654 000)
(6 985 000)
(7 348 000)
(7 727 000)
(8 098 000)
(8 469 000)
(8 953 000)
(9 332 000)
(9 735 000)
(10 122 000)
(11 631 000)
(12 018 000)
(12 437 000)
(12 832 000)
(13 760 000)
(14 203 000)
(15 236 000)
[15 689 100]
(26 600 000)
(27 495 000)
(28 455 000)
(29 463 000)
(30 447 000)
(31 415 000)
(32 867 000)
(33 867 000)
(34 964 000)
(35 980 000)
(38 811 000)
(39 699 000)
(40 683 000)
(41 594 000)
(44 578 000)
(45 619 000)
(47 595 000)
(48 579 000)
(107 651 000)
(110 103 000)
(112 821 000)
(115 337 000)
(126 331 000)
(129 339 000)
(133 122 000)
(135 616 800)
(548 176 700)
(559 647 500)

Notes:
^aUncertainty of the listed value is unknown.

If you did not find the data you need, please inform the ASD Team.

NIST Physical Measurement Laboratory