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-The nature of the intrinsic luminescence of the lutetium aluminum garnet Lu 3 Al 5 O 12 (LuAG) has been analyzed on the basis of time-resolved spectral kinetic investigations upon excitation of two model objects, LuAG single crystals and single-crystal films, by pulsed X-ray and synchrotron radiations. Due to the differences in the mechanisms and methods of crystallization, these objects are characterized by significantly different concentrations of Lu Al antisite defects. The energy structure of luminescence centers in LuAG single crystals (self-trapped excitons (STEs), excitons localized near antisite defects, and Lu Al antisite defects) has been established. For single-crystal LuAG films, grown by liquid-phase epitaxy from a Pb-containing flux, the energy parameters of the following luminescence centers have been determined: STEs in regular (unperturbed by the presence of antisite defects) sites of the garnet lattice and excitons localized near Pb 2+ ions. The structure of the luminescence centers, related to the background emission of impurity Pb 2+ ions, has also been established in the UV and visible ranges. It is suggested that, in contrast to the two-halide hole self-trapping, a self-trapped state similar to STEs in simple oxides ( Al 2 O 3 , Y 2 O 3 ) is formed in LuAG; this state is formed by self-trapped holes in the form of singly charged O -ions and electrons localized at excited levels of Lu 3+ cations. PACS numbers: 78.55.-m

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-Luminescence properties of a pure CdWO 4 crystal and a CdWO 4 :Mo crystal doped with molybdenum in different concentrations have been investigated. The effect of molybdenum impurity on the intrinsic luminescence of CdWO 4 has been found, and the role of the impurity in the formation of new luminescence centers has been investigated. The features of the formation of the intrinsic and impurity luminescence excitation spectra of CdWO 4 and CdWO 4 :Mo crystals in the fundamental-absorption region have been considered. The reflection spectra of the CdWO 4 crystal have been investigated taking into account the crystal structure anisotropy. PACS numbers: 78.55.-m, 78.40.-q

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