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Critically Evaluated Energy Levels and Spectral Lines of Singly Ionized Indium (In II)



Alexander Kramida


A comprehensive list of the best measured wavelengths in the In II spectrum has been compiled. Uncertainties of the wavelength measurements have been analyzed, and existing inconsistencies have been resolved. An optimized set of fine-structure energy levels that fits all observed wavelengths has been derived. Uncertainties of the energy level values have been reduced by an order of magnitude. An improved value of the ionization limit of In II has been determined by fitting quantum-defect and polarization formulas for several series of levels. Intensities of lines observed by different authors have been analyzed and converted to a uniform scale. A set of recommended values of radiative transition rates has been critically compiled, and uncertainties of these rates have been estimated. The hyperfine structure interval in the 5s 2S ground state of In III has been determined from the measurements of the 5sng and 5snh series in In II.
Journal of Research (NIST JRES) - 118.004
Report Number


Atomic energy levels, spectral lines, ionization potentials, transition probabilities, hyperfine structure, singly ionized indium


Kramida, A. (2013), Critically Evaluated Energy Levels and Spectral Lines of Singly Ionized Indium (In II), Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 26, 2024)


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Created January 14, 2013, Updated November 10, 2018