Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

New FTS Measurements, Optimized Energy Levels and Refined VUV Standards in the Ne III Spectrum



Alexander Kramida, Gillian Nave


All observed spectral lines of Ne III in the range 204 to 36 m have been compiled and critically evaluated. An optimized level scheme has been derived from the total list of observed lines. Relative positions of about 70 of known energy levels of Ne III have been determined with improved accuracy compared to previous studies. Excitation energies of almost all excited levels have been revised by 0.5 1.5 cm-1. Thirty two precise wavelength standards have been derived with well-defined uncertainties in the region 210 1030 . Concepts of error current and covariance matrix have been implemented in a computational algorithm that permits one to derive the uncertainties of Ritz wavelength standards obtained from a set of least-squares-optimized energy levels. Nine new energy levels have been found, and 16 new transitions have been identified in the EUV range. The ionization potential has been revised by 2 cm-1. The new value is 511541 4 cm-1 (63.4230 0.0005 eV).
European Journal of Physics
37 No 1


energy levels, ionization potential, level optimization, Ne2+, oxygen-like neon, spectral lines, transition probabilities, VUV standards, wavelengths


Kramida, A. and Nave, G. (2006), New FTS Measurements, Optimized Energy Levels and Refined VUV Standards in the Ne III Spectrum, European Journal of Physics (Accessed June 13, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created January 1, 2006, Updated February 17, 2017