| Abstract: | Although it has been recognized for many years that the spectra of lanthanoid ions can provide useful information about short range phenomena in the neighborhood of these inos in a solid material, lanthanoid spectroscopy has only infrequently been used for studying complex materials because of the problem of line-sorting the complex spectra that are obtained. The advent of convenient tuneable lasers has eliminated this problem. By selectively exciting probe ion luminescence (SEPIL), it is possible to obtain fluorescence and excitation spectra from a single kind of crystallographic environment. Two applications of this method are dicussed in this paper. The first application is the study of the defect chemistry of fluorite materials (compounds with CaF2 lattice). It is shown how this method can provide unique information about the solid state chemistry, thus clarifying many of the unexplained behaviors of this important class of material. The second application shows application shows how ultra-trace analysis can be carried out by causing an association between an analyte ion and a fluorecent probe ion. The unique crystal field levels of a probe ion associated with a particular analyte can be selectively excited so that traces of the ion to be analyzed can be detected with very high selectivity and with very low detection limits. |
