Evaluation of Electrostatic Energy Levels of f6

Abstract

The 119 electrostatic energy levels for an nf⁶ configuration have been calculated for three different sets of Slater F_k ratios: 4f⁶ hydrogenic—F₄/F₂=0.1381, F₆/F₂=0.01511; 5f⁶ hydrogenic—F₄/F₂=0.1422, F₆/F₂=0.0161; and 5f⁶ based on a Hartree‐Fock calculation for the normal uranium atom—F₄/F₂=0.159, and F₆/F₂=0.0204. A tentative theoretical analysis of the absorption spectra of Eu IV can be made by using ζ=1360 cm⁻¹ and F₂=370 cm⁻¹. The results of our work show clearly that the intermediate field matrices are essential to a quantitative analysis of the Eu IV and Am IV spectra, and that Zeeman studies are needed to identify certain levels.