![]() |
CiteULike | ![]() |
samuelpaul83's CiteULike | ![]() |
![]() |
|
![]() |
Register | ![]() |
Log in | ![]() |
Optical Absorption Intensities of Rare-Earth Ionsby: B. R. Judd
|
Reviews
[Write a review of this article]
Find related articles from these CiteULike users
Find related articles with these CiteULike tags
Posting History
AbstractElectric dipole transitions within the 4 f shell of a rare-earth ion are permitted if the surroundings of the ion are such that its nucleus is not situated at a center of inversion. An expression is found for the oscillator strength of a transition between two states of the ground configuration 4 f N ; on the assumption that the levels of each excited configuration of the type 4 f N n ′ d or 4 f N n ′ g extend over an energy range small as compared to the energy of the configuration above the ground configuration. On summing over all transitions between the components of the ground level ψ J and those of an excited level ψ ′ J ′ ; both of 4 f N ; the oscillator strength P corresponding to the transition ψ J →ψ ′ J ′ of frequency ν is found to be given by P =Σ T λ ν(ψ J ∥ U (λ) ∥ψ ′ J ′ ) 2 ; where U (λ) is a tensor operator of rank λ; and the sum runs over the three values 2; 4; and 6 of λ. Transitions that also involve changes in the vibrational modes of the complex comprising a rare-earth ion and its surroundings; provide a contribution to P of precisely similar form. It is shown that sets of parameters T λ can be chosen to give a good fit with the experimental data on aqueous solutions of NdCl 3 and ErCl 3 . A calculation on the basis of a model; in which the first hydration layer of the rare-earth ion does not possess a center of symmetry; leads to parameters T λ that are smaller than those observed for Nd 3+ and Er 3+ by factors of 2 and 8; respectively. Reasons for the discrepancies are discussed.
BibTeX record
RIS record