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Spectrum and Energy Levels of Four-Times Ionized Yttrium (Y V



Joseph Reader


We present an extended analysis of the spectrum of four-times-ionized yttrium Y V. The analysis is based on spectrograms made with sliding-spark discharges on 10.7 normal- and grazing-incidence spectrographs. The measurements cover the region 184-2549 Å. The results revise levels for this spectrum by Zahid-Ali et al. (J. Phys. B 1975, 8, 185) and by Ateqad at al. (J. Phys. B 1984, 17, 1727). 570 lines were classified as transitions between 23 odd-parity and 90 even-parity levels. The 4s24p5, 4s4p6, 4s24p44d, 5s, 5p, 5d, 6s configurations are now complete. Results for the 4s24p46d and 7s configurations are tentative. Ritz-type wavelengths were determined from the optimized energy levels, with uncertainties as low as ±0.0004 Å. The observed configurations were interpreted with Hartree-Fock calculations and least-squares fits of the energy parameters to the observed levels. Oscillator strengths for all classified lines were calculated with the fitted parameters. The results are compared with values for the level energies, percentage compositions, and transition probabilities from recent ab initio MCDF calculations. The ionization energy was revised to 607 760±300 cm-1 (75.35±0.04 eV).


yttrium, ionic spectrum, vacuum ultraviolet, wavelengths, energy levels, transition probabilities, parametric calculations, ionization energy


Reader, J. (2016), Spectrum and Energy Levels of Four-Times Ionized Yttrium (Y V, Atoms, [online], (Accessed May 26, 2024)


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Created December 21, 2016, Updated July 3, 2023