NIST Atomic Ionization Energies Output

NIST Physical Measurement Laboratory

NIST Atomic Spectra Database Ionization Energies Data Er (all spectra) 68 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)
49 262
[96 110]
[183 090]
[342 140]
[525 100]
(777 000)
(918 000)
(1 060 000)
(1 271 000)
(1 424 000)
(1 619 000)
(1 892 000)
(2 160 000)
(2 340 000)
(2 510 000)
(2 780 000)
(3 070 000)
(3 350 000)
(3 630 000)
(3 920 000)
(4 200 000)
(4 480 000)
(6 210 000)
(6 533 000)
(6 880 000)
(7 251 000)
(7 606 000)
(7 977 000)
(8 437 000)
(8 808 000)
(9 211 000)
(9 582 000)
(11 050 000)
(11 421 000)
(11 840 000)
(12 227 000)
(13 107 000)
(13 534 000)
(14 542 000)
[14 990 000]
(25 463 000)
(26 334 000)
(27 270 000)
(28 270 000)
(29 230 000)
(30 181 000)
(31 585 000)
(32 569 000)
(33 633 000)
(34 633 000)
(37 416 000)
(38 295 000)
(39 247 000)
(40 150 000)
(42 981 000)
(43 998 000)
(45 933 000)
(46 901 000)
(104 191 000)
(106 602 000)
(109 272 000)
(111 748 000)
(122 161 000)
(125 105 000)
(128 815 000)
(131 263 200)
(531 101 910)
(542 339 100)

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