Theoretical calculations of energies, and radiative rates for parity-forbidden transitions within the 4f³ configuration in La-like ions Pr²⁺ and Nd³⁺

The observed 4f³ energy levels of La isoelectronic sequence ions Pr²⁺ and Nd³⁺ were analyzed using a standard f-shell free-ion Hamiltonian. The root mean square (rms) deviation of 13.54 cm⁻¹, 6.17 cm⁻¹ between calculated and observed energies were obtained from the fit of 16 free-ion parameters to 38 levels for Pr²⁺, and to the complete set of 41 levels for Nd³⁺, respectively. Then, the fitted values of free-ion parameters were used to compute wavelengths, oscillator strengths, and transition rates for the forbidden magnetic dipole and electric quadrupole transitions between the 4f³ levels in Pr²⁺ and Nd³⁺ La-like ions. Detailed comparisons with other available theoretical data are also reported and discussed in this work. Copyright © 2015 Published by Elsevier B.V.