Intrinsic emission of complex oxides with garnet structure was studied by means of the analyses of the time-resolved luminescence spectra and decay kinetic for single crystals (SC) and single-crystalline films (SCF) of Y 3 Al 5 O 12 (YAG) and Lu 3 Al 5 O 12 (LuAG) garnets under excitation by the pulse X-ray and synchrotron radiation at 8 -300 K. YAG and LuAG SC and SCF are characterized by significantly different concentration of the Y Al and Lu Al antisite defects (AD) due to the substantial difference in the conditions of their crystallization. For this reason, LuAG and YAG SC and SCF are very useful model objects for the study of nature of the intrinsic emission of these oxides, consisting of the excitons and AD luminescence.

We discuss the Raman scattering of thermally oxidized gallium selenide (GaSe) and indium selenide (InSe) single crystals. It has been established that the oxidation mechanisms of these compounds are rather different. For InSe, an increase of the oxidation temperature leads to the formation of (SeO 4 ) complexes. For GaSe, it is characteristic that only Ga 2 O 3 is formed as an oxygen-containing phase during the oxidation. The presence of the Me 2 Se 3 phase (where Me is Ga or In) in its own oxide is common for both of the semiconductors.

Luminescent properties and the energy transfer from host to Ce 3+ ions are analyzed in single crystalline films (SCF) of YAlO 3 :Ce (YAP:Ce), Y 1−x Lu x AP:Ce (YLuAP:Ce) and LuAlO 3 :Ce (LuAP:Ce) perovskites in comparison with their single crystal (SC) analogues using the timeresolved luminescence spectroscopy under synchrotron radiation excitation. It is shown that the main peculiarity of luminescent properties of YAP:Ce, YLuAP:Ce and LuAG:Ce SCF is determined by the extremely low concentration of Y Al and Lu Al antisite defects and vacancy-type defects in SCF as compared to SC. The advantages of phosphors based on (Y-Lu)AP:Ce SCF are due to the absence of emission and trapping centers in these SCF which are connected with the above mentioned bulk crystal defects.

Bi-doped Lu3Al5O12 (LuAG) single crystalline films (SCFs) of thickness within 8–31 µm were grown by the liquid-phase epitaxy method onto Y3Al5O12 (YAG) single crystal substrates using a melt solution based on a Bi2O3 flux. Their characteristics were compared with YAG : Bi SCFs grown at the same conditions. The concentration of Bi3+ ions in LuAG : Bi and YAG : Bi SCFs was varied by changing the growth temperature in the ranges 0.05–0.18 at% and 0.13–0.57 at%, respectively. The absorption, luminescence and scintillation properties of these SCFs noticeably depend on the Bi3+ concentration. Luminescence spectra of both LuAG : Bi and YAG : Bi SCF consist of two broad emission bands in the UV and visible (VIS) spectral ranges peaking at 4.155–4.085 eV and 2.45–2.66 eV, respectively. Both the UV and VIS luminescence show complex non-exponential decays. Under 241Am α-particle excitation the photoelectron yield of the best performing LuAG : Bi (0.18 at%) and YAG : Bi (0.13 at%) SCFs is about 15% and 21%, respectively, of that of the reference YAP : Ce single crystal.

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