Energy levels, radiative rates and lifetimes for transitions in Br-like ions with 38 ⩽ Z ⩽ 42

Abstract

Energy levels and radiative rates for transitions in five Br-like ions (Sr IV, Y V, Zr VI, Nb VII and Mo VIII) are calculated with the general-purpose relativistic atomic structure package (grasp). Extensive configuration interaction has been included and results are presented among the lowest 31 levels of the 4s 2 4p 5 , 4s 2 4p 4 4d and 4s4p 6 configurations. Lifetimes for these levels have also been determined, although unfortunately no measurements are available with which to compare. However, recently theoretical results have been reported by Singh et al [Phys. Scr. 88 (2013) 035301] using the same grasp code. But their reported data for radiative rates and lifetimes cannot be reproduced and show discrepancies of up to five orders of magnitude with the present calculations.

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

“…The main difference between the results of [17,18] and our present results is that the energies of the levels designated 4s 2 4p 4 ( 3 P)4d 2 P 1/2 (index 28) and 4s 2 4p 4 ( 1 D)4d 2 S 1/2 (index 30) are reversed in order of energy. That is, the level with index 28 corresponds to our level 4d51, and the level with index 30 corresponds to our level 4d41.…”

“…Comparisons of our present results with those of the ab initio calculations of [17,18] are given in Tables 8-10. The index numbers for the levels in these tables are those used in [17,18].…”

“…Singh et al [17] used a multiconfiguration Dirac-Fock (MCDF) approach to make calculations for transitions within the n = 4 complex; 4s 2 4p 5 , 4s4p 6 , 4s 2 4p 4 4d. Aggarwal and Keenan [18] used the General-purpose Relativistic Atomic Structure Package (GRASP) for calculations within the same complex of n = 4 configurations. Both calculations are based on new versions of the Grant atomic structure code.…”

“…The index numbers for the levels in these tables are those used in [17,18]. The wavelengths for Aggarwal and Keenan [18] in Table 8 are differences of the GRASP3 energies in their Table 3.…”

“…The wavelengths for Aggarwal and Keenan [18] in Table 8 are differences of the GRASP3 energies in their Table 3. It should be noted that the level with index 25 in [17] is misprinted 4s 2 4p 4 ( 1 D)4d 2 P 3/2 ; it should be 4s 2 4p 4 ( 1 S)4d 2 D 3/2 , as given in [18].…”