Production of the oxyfluorides of holmium,erbium, and ytterbium and study of their crystal-chemical properties

Journal of Structural Chemistry -     

Optical spectra of CaF2(Tb) crystals

The luminescence and absorption spectra of fluorite crystals, alloyed with terbium fluorides, oxyfluorides, and oxides at concentrations of 0.01 to 5 mol.% were studied. The change in the optical spectra was studied as a function of the chemical composition of the alloy addition and also as a function of the concentration. It is proposed that the change with the concentration in the spectra of the crystals takes place as a consequence of mutual interactions between the ions with formation of cation pairs. It was observed that the ratio of the relative luminescence intensities of the crystals to the absorption coefficient changes nonlinearly with the concentration of the alloying addition. The problem of an interaction between an isomorphic admixture and crystal defects is discussed.In conclusion, the authors express their gratitude to E. V. Sobolev and M. V. Konovalova for help in the work.