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[en] Oscillatory spectra of double oxides of rare earths of composition LnLuO3 (Ln-Ce, Pr, Nd) were investigated. Using theoretical calculation, which has been carried out for CeLuO3 in the approximation of polymeric chains of the valence-power field method, reference of experimental spectra has been suggested, frequency branches have been plotted, and the power field of crystals has been estimated
[en] The IR absorption spectra (40Q-1200 cm-1) of LuPO4, activated by Nd3+, Eu3+, Er3+, are obtained. The introduction of active ions of r.e.e. does not cause noticeable distortions of low resolved spectra. During precise investigation of spectra with a high resolution the redistribution of the line intensities, appearance of bends, change of the shape and non-monotonous shift of absorption line position, especially noticeable when Eu3+ and Er3+ are introduced, are observed. Such behaviour of the spectra is explained by the deformation of coordination polyhedron of r.e.e. cation and the change of the force constants when it is substituted for by r.e.e. ion with a higher number of 4f-electrons. A preferable sensitivity of antisymmetric valent vibration νsub(as) (F) of the anion PO43- to the change of the active ion concentration is pointed out. Non-monotonous character of concentrational behaviour of IR spectra is connected with the complexity of interaction in ternary systems
[en] The identification and characterization of the carbides Yb15C19 and Lu15C19 have been established by X-ray diffraction analysis. They have the same crystal structure as Sc15C19. As these phases are transitional between the monocarbides and the dicarbides, we call them 'transition carbides'
[fr]L'identification et la caracterisation des carbures Yb15C19 et Lu15C19 ont ete etablies par des methodes radiocristallographiques et metallographiques. Ces carbures, isotypes de Sc15C19, representent une transition entre les monocarbures et les dicarbures. C'est pourqoi nous les appelons 'carbures de transition'
[en] Consideration is given to results of investigating break-down of lutetium oxide films in silicon MGD-structures, when using linearly growing voltage. Dependences of break-down intensity of dielectric films on the rate of sawtooth voltage growth on the structure, dielectric thickness and temperature were studied
[en] The present work is devoted to un traditional task of the high-precision electron spectroscopy, namely, to the effects of space-time self-organization in radioactive lutetium oxide film with thickness up to 10000 Angstrom units, deposited on a metal backing. When the spectra of internal conversation electrons (ICE) of long-lived lutetium isotopes (the half lives from 2 d to 3,3 yr) were obtained, the complex structure of ICE peaks and its time-dependence was found. The simultaneously using of the nuclear spectroscopic, auto electron and Auger-spectroscopic methods was applied first time in world practice for studying of this film system. The received results shows, the high-precision beta-spectroscopy can be applied to the following problems: - Investigation of condensed matter, its structure of inner and surface field, order of symmetry of solid state quasicrystals matrix; - Study on processes of formation, stability and destruction of ordered space and time structures in complex nonequilibrium systems. 5 refs
[en] The true potential energy curve for the electronic ground state of the LuF molecule has been constructed by the Rydberg-Klein-Rees method. By curve fitting of the five-parameter Hulburt-Hirschfelder empirical potential function, the dissociation energy Dsub(o)sup(o) of LuF is found to be 402+-10 KJ molsup(-1). The force constant of the electronic ground state of LuF molecule indicates that this value is of the correct order. (author)
[en] The occupancy of C2 and S6 sites by Eu3+ ions in nanocrystalline powders and microcrystalline ceramics of Lu2O3 prepared from these powders was studied by Moessbauer spectroscopy. It was proved that in nanopowders prepared by vigorous combustion syntheses the occupancy of the C2 and S6 sites by Eu3+ is almost random, with only a very limited preference for the former. For ceramic specimens formed at 1750 deg. C within a few hours, it was found that Eu3+ ions strongly prefer to enter the Lu2O3 host at the C2 site. We concluded that thermodynamically the non-centrosymmetric site C2 is preferred to the S6 site by Eu3+. However, if the formation of crystallites is very fast, like in combustion syntheses, the Eu3+ ions are entrapped into the two sites nearly randomly