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Spectroscopic Data for Neutral Francium (Fr I)



Jean E. Sansonetti


Energy levels and hyperfine structure constants have been compiled for the sixteen longest-lived isotopes of francium (Z=87). Wavelengths with classifications and transition probabilities are also tabulated for 212Fr. In addition, the ionization energy is included for isotopes in which a sufficient number of levels have been measured.
J. Phys. & Chem. Ref. Data (JPCRD) -


atomic spectra, energy levels, francium, hyperfine structure, wave numbers, wavelength tables, wavelengths


Sansonetti, J. (2018), Spectroscopic Data for Neutral Francium (Fr I), J. Phys. & Chem. Ref. Data (JPCRD), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 20, 2024)
Created November 14, 2018