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Extended Analysis of the Spectrum of Singly Ionized Chromium (Cr II)
Published
Author(s)
Craig J. Sansonetti, Gillian Nave
Abstract
We have made new observations of the spectrum of singly-ionized chromium (Cr II) in the region 2850 Angstrom to 37900 Angstrom with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. These data extend our previously reported observations in the near ultra-violet region. We present a comprehensive list of more than 5300 Cr II lines classified as transitions among 456 even and 457 odd levels, 179 of which are newly located in this work. Using highly excited levels of the 3d4(5D)5g, 3d4(5D)6g, and 3d4(5D)6h configurations, we derive an improved ionization energy of 132971.02(12) cm -1 (16.486305+/-0.000015eV).
Sansonetti, C.
and Nave, G.
(2014),
Extended Analysis of the Spectrum of Singly Ionized Chromium (Cr II), Astrophysical Journal Supplement Series, [online], https://doi.org/10.1088/0067-0049/213/2/28, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=915717
(Accessed October 19, 2025)