Effect of electron correlation on the forced electric dipole transition probabilities in f^N systems

Abstract

Results of model studies of the impact of electron correlation on the forced electric dipole transition probabilities between states of the 4f^N configuration are reported for the [³ P]₀↔[³ F]₄, [³ H]₄ transitions in Pr³⁺: LaCl₃ and for [⁷ F]₀↔[⁵ D]₂, [⁷ F]₁↔[⁵ D]₁ hypersensitive transitions in Eu³⁺: LaCl₃. For the former system the correlation effects cause a modification of the Judd-Ofelt results by 40–95 per cent, whereas for the latter the probability changes by as much as two orders of magnitude. The great changes found in the case of hypersensitive transitions suggest that electron correlation effects may belong to the most important factors determining the nature of these transitions. Several types of effective correlation operators are considered and their relative importance is discussed. The results indicate that intermediate configurations including g orbitals are very important for the description of correlation effects.