Vacuum ultraviolet photoluminescence of NaMgF3:Sm and NaMgF3:Sm,Ce: energy levels of the lanthanides in NaMgF3:Ln compounds

Abstract The luminescence properties of NaMgF 3 :Sm and NaMgF 3 :Ce,Sm were studied in the vacuum ultraviolet spectral region. Excitation bands corresponding to the charge transfer processes F − → Sm 3+ , O 2− → Sm 3+ , and O 2− → Ce 3+ , and the energy transfer processes Ce 3+ → Sm 3+ and O 2− → Sm 3+ , were observed. The energies of the Sm 3+ charge transfer transitions and the crystal field split Ce 3+ 4 f 0 5 d 1 transitions were used to construct a complete host referred binding energy diagram for the series of lanthanide-doped NaMgF 3 :Ln compounds. We demonstrate that the optical and luminescence properties predicted by the binding energy diagram are in good agreement with those predicted by the binding energy diagram constructed via the alternative impurity-informed method, and all available experimental data regarding the NaMgF 3 :Ln compounds. We demonstrate that NaMgF 3 :Ln compounds are model systems for the study of charge trapping phenomena and divalent lanthanide luminescence. Ultimately, we validate that the impurity-informed method can be used to establish the energy levels of lanthanides in fluoride systems.