A systematic analysis of the spectra of the lanthanides doped into single crystal LaF3

Abstract

The optical spectra of the lanthanides doped into single crystal LaF 3 have been interpreted in terms oftransitions within 4fN configurations. Energy matrices combining free-ion terms with a crystal field for an approximate model which assumes C 2v instead of the actual C 2 site symmetry were diagonalized. Excellent correlations were obtained between experimental transition energies and the computed level structures. We also report the results of previously unpublished experimental spectroscopic investigations ofNd 3 + and Sm 3 +:LaF 3 , as well as predicted energy levels for Pm3+:LaF 3 . The spectroscopic data for each ion were independently interpreted using an effective-operator model, then the model parameters were intercompared. Systematic trends have been identified, and a comprehensive energy level diagram is presented.

Spectroscopy of High‐Energy States of Lanthanide Ions

“…We illustrate this method for the crystal-field and spin-orbit parameters for the 4f 1 and 5d 1 configurations of Ce 3+ in LiYF 4 . Further details and calculations for other hosts will be presented elsewhere.…”

“…Thus, the positions of the electronic multiplets are quite similar in different crystals, leading to the useful concept of a "Dieke diagram", which summarises the energy levels of the entire lanthanide series [2,4,5] Transitions between 4f N states are parity forbidden, so the transitions are rather weak, consisting of magnetic-dipole and "forced" electric-dipole transitions. The latter are parametrized according to the "Judd-Ofelt" approach [30,31,32].…”

“…The parametric models that were developed in the 1960s [1,2,3] gained further sophistication through the 1970s and 1980s (see, for example, Ref [4]). For a recent review see Ref.…”

5f−6dorbital hybridization of trivalent uranium in crystals of hexagonal symmetry: Effects on electronic energy levels and transition intensities

“…1-3͒ has been applied successfully to modeling the electronic energy-level structures of the 4f n configurations of lanthanide ions in crystalline solids. [4][5][6][7] In the conventional framework of CFT, an effective Hamiltonian including both free-ion interactions and ion-lattice interactions is usually parameterized by fitting the calculated energy levels to those observed in spectroscopic experiments. [6][7][8][9] This method is also effective for isolated multiplets of the 5f n configurations of actinide ions in crystals where configuration coupling is weak.…”

“…[4][5][6][7] In the conventional framework of CFT, an effective Hamiltonian including both free-ion interactions and ion-lattice interactions is usually parameterized by fitting the calculated energy levels to those observed in spectroscopic experiments. [6][7][8][9] This method is also effective for isolated multiplets of the 5f n configurations of actinide ions in crystals where configuration coupling is weak. [10][11][12][13] Based on the symmetry properties of crystal field, the intraconfiguration crystal-field interactions are induced by the crystal-field operators of even ranks ͑B q k , k =2,4,6͒, whereas the odd ranks of crystal-field operators ͑k =1,3,5͒ only couple the free-ion states of two configurations with different parities.…”