Energy levels and transition rates for the boron isoelectronic sequence: Si X, Ti XVIII – Cu XXV

Abstract

Relativistic configuration interaction (RCI) 2 4l (l = 0, 1, 2 and l = 0, 1, 2, 3) in boron-like ions Si X and Ti XVIII to Cu XXV. Electron correlation effects are represented in the wave functions by large configuration state function (CSF) expansions. States are transformed from j j-coupling to LS -coupling, and the LS -percentage compositions are used for labeling the levels. Radiative electric dipole transition rates are given for all ions, leading to massive data sets. Calculated energy levels are compared with other theoretical predictions and crosschecked against the Chianti database, NIST recommended values, and other observations. The accuracy of the calculations are high enough to facilitate the identification of observed spectral lines.

MCDHF Calculations and Beam-Foil EUV Spectra of Boron-Like Sodium Ions (Na VII)

“…Disregarding these levels, the average relative difference between the calculated and experimental energy values is less than 0.018 %. This is in line with the accuracy found for other ions in the B-like sequence [52,55]. Our computations result in more than 1500 calculated transitions with a transition rate higher than A = 10 6 s −1 (an arbitrary cut-off) and wavelengths that range from just below 7 nm to beyond 900 nm.…”

“…Recently Rynkun and Jönsson et al have calculated (by the relativistic configuration interaction method) n = 2 levels of B-like ions from elements N through Zn, as well as transitions between these levels [52][53][54][55]. They have compared their calculated level energies with the results of other advanced calculations and with databases and experimental data for Si X [51], and they find good agreement.…”

Hyperfine structures and Landé gJ-factors for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions from

“…In this work calculations were carried out by parity and configuration, that is, wave functions for all states belonging to a specific configuration were determined simultaneously in an EOL calculation [24]. The EOL scheme has shown to be surprisingly efficient, and a balanced description of a large number of fine-structure states, belonging to one or more configurations, can be obtained in a single calculation [37,38]. The expansions for the ASFs were obtained using the active set method [39].…”

Validation and Implementation of Uncertainty Estimates of Calculated Transition Rates

“…Together with sophisticated and refined theoretical methods, calculated properties of more complex atomic systems often reveal astonishing accuracy when validated against experimental observations and the term "spectroscopical accuracy" is used and justified [1][2][3]. This term refers to the high accuracy of experimental transition energies, and the level energies derived from these.…”