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Optical spectroscopy of complex open 4$d$-shell ions Sn$^{7+}$-Sn$^{10+}$

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 نشر من قبل Francesco Torretti
 تاريخ النشر 2016
  مجال البحث فيزياء
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We analyze the complex level structure of ions with many-valence-electron open [Kr] 4$d^textrm{m}$ sub-shells ($textrm{m}$=7-4) with ab initio calculations based on configuration-interaction many-body perturbation theory (CI+MBPT). Charge-state-resolved optical and extreme ultraviolet (EUV) spectra of Sn$^{7+}$-Sn$^{10+}$ ions were obtained using an electron beam ion trap. Semi-empirical spectral fits carried out with the orthogonal parameters technique and Cowan code calculations lead to 90 identifications of magnetic-dipole transitions and the determination of 79 energy ground-configuration levels, questioning some earlier EUV-line assignments. Our results, the most complete data set available to date for these ground configurations, confirm the ab initio predictive power of CI+MBPT calculations for the these complex electronic systems.



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