The relationship between perturbation theory and direct calculations of rare-earth transition intensities
We use a simpliﬁed calculation to demonstrate the equivalence between three diﬀerent methods for calculating transition line strengths. These calculations demonstrate the complex interplay between spin-orbit and correlation contributions to two-photon transitions in rare-earth ions.
Journal of Alloys and Compounds
Reid, Michael; Burdick, Gary; and Kooy, H, "The relationship between perturbation theory and direct calculations of rare-earth transition intensities" (1994). Faculty Publications. 70.