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Revision of the ionization energy of neutral carbon
Published
Author(s)
W L. Glab, Haris Kunari, Alexander Kramida
Abstract
This publication describes a re-analysis of previously published data on neutral carbon (C I) utilizing critically examined and improved values for the line energies of the absorption spectrum of molecular iodine to calibrate the transition energies of C I absorption lines originating from the 1s22s22p3s 3P°2 level and terminating on highly excited Rydberg states of the 1s22s22pnp 3D3 series, which converges on the first excited fine-structure level of the ionic ground configuration. Additional use of improved energy values for the 1s22s22p3s 3P°2 level, the fine-structure interval of the ionic ground state, and sophisticated modern fitting techniques lead to a new value of the ionization energy of neutral carbon with 9 times the precision of previous work, 90820.348(9) cm−1, as well as a table of predicted values for the energies of not yet observed states in the series.
Citation
Journal of Physics B-Atomic Molecular and Optical Physics
Glab, W.
, Kunari, H.
and Kramida, A.
(2018),
Revision of the ionization energy of neutral carbon, Journal of Physics B-Atomic Molecular and Optical Physics, [online], https://doi.org/10.1088/2399-6528/aac421, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=925382
(Accessed October 9, 2025)