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Re-optimized energy levels and Ritz wavelengths of 198Hg I



Alexander Kramida


Energy levels and observed spectral lines of 198Hg I were recently compiled at the National Institute of Standards and Technology (NIST) [E. B. Saloman, J. Phys. Chem. Ref. Data 35, 1519 (2006)]. In that compilation, the energy level values were optimized on the basis of selected measured wavelengths of 105 observed spectral lines. Our new analysis of those measurements revealed large inconsistencies in the assessment of measurement uncertainties in the NIST compilation. This affected the values and uncertainties of the energy levels as well as the Ritz wavelengths derived from them. In the present work we revise the level optimization and construct improved and internally consistent level and line lists with reliable Ritz wavelengths that can be used as secondary wavelength standards in the wide range from 1200 Å to 65000 Å.
Journal of Research (NIST JRES) -


atomic spectra, standard wavelength, energy levels, reference data, mercury atom


Kramida, A. (2011), Re-optimized energy levels and Ritz wavelengths of 198Hg I, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 26, 2024)


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Created May 10, 2011, Updated April 7, 2024