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[en] Generalization of published and original investigations of structure, spectral-luminescent and generation characteristics of hexaaluminates of the rare-earth elements has shown that they possess optimal for luminophores and laser crystals combination of physicochemical properties. They are characterized by high radiation, thermal and chemical stability, high luminescence quantum yield and weak concentration quenching. The variety of structural types substantial reciprocal solubility permit to vary compositions and properties of hexaaluminates in wide range. The perspective of started investigations on relation of optical and radiation-stimulated properties to the features of crystal structure in the series of complicating oxide systems: simple oxides, mono and polyaluminates is shown

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[en] Photoluminescence of Eu³⁺ ions in lanthanum-magnesium hexa-aluminate has been investigated for the first time. Concentration and temperature dependences of luminescence intensity and Lasub(1-x)Eusub(x)MgAlsub(11)Osub(19) spectra structure at x=0.01-1.0 have been studied. Existence of several types of luminescence centres(LC) has been established. High-symmetry LCsub(s)(Dsub3h)) are predominantly revealed on excitation to the band of charge transfer in luminescence spectra. Theoretical-group analysis of europium luminescence spectra structure for possible LC(s) in hexa-aluminate with the structural type of magnetoplumbite (P6₃/mmc space group) has been conducted

[en] For the first time (up to 15 mm³) Cesub(1-x)Tbsub(x)MgAlsub(11)Osub(9) crystals (ACMT) are obtained using the cold crucible method. Fine-crystalline samples are also prepared using zone melting, i.e. an actual possibility of preparing hexaaluminate monocrystals with a high rare-earth ion concentration (about 3x10²¹cm^-3) is shown. A roentgenometric ACMT ''certificate'' is drawn, and full crystallographic identity of samples prepared by melting and sintering of an oxide stoichiometric mixture is shown. It is established that the process of ACMT hexaaluminate preparation goes through stages of cerium and magnesium monoaluminate formation. The studied compound melts congruently and have no polymorphous transformations. The prepared hexaaluminate crystals can be recommended for new microcrystal application in integral optics under present development