caa a22 4500 467923612 CHVBK 20180406152923.0 cr unu---uuuuu 170328e20061001xx s 000 0 eng 10.1134/S1087659606050014 doi (NATIONALLICENCE)springer-10.1134/S1087659606050014 Raman and dielectric spectra of the glass and single crystal of the composition Li2Ge7O15 in the frequency range 3-1000 cm−1: II. The influence of phase separation [Elektronische Daten] [V. Sigaev, S. Lotarev, E. Smelyanskaya, P. Sarkisov, A. Volkov, G. Komandin, V. Koltashev, V. Plotnichenko] The Raman spectra of Li2O · 7GeO2 glasses, which are heat treated under different conditions at temperatures near the temperature corresponding to the first exothermal peak in the DTA curve, are measured in the frequency range 20-1100 cm−1. A comparative analysis of the measured spectra with the use of the data available in the literature and the X-ray diffraction results demonstrates that the glass undergoes phase separation and that phases of compositions close to GeO2 and Li2O · 4GeO2 precipitate at the initial stage. The ordering of both phases varies significantly within the sample and, on the average, is substantially higher than that in the initial glass. This confirms the known assumptions made by researchers that crystal nuclei with a Li2O · 4GeO2 structure arise during heat treatment of lithium germanate glasses. At the phase separation stage under investigation, the phases are formed as nanoinhomogeneities that only slightly affect the transparency and, in the course of heat treatment, increase in size with a further ordering of the structure. Pleiades Publishing, Inc., 2006 Sigaev V. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut Lotarev S. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut Smelyanskaya E. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut Sarkisov P. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut Volkov A. Institute of General Physics, Russian Academy of Sciences, Leninskii pr. 53, 117924, Moscow, Russia aut Komandin G. Institute of General Physics, Russian Academy of Sciences, Leninskii pr. 53, 117924, Moscow, Russia aut Koltashev V. Research Center of Fiber Optics, Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, 119991, Moscow, Russia aut Plotnichenko V. Research Center of Fiber Optics, Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, 119991, Moscow, Russia aut Glass Physics and Chemistry Nauka/Interperiodica 32/5(2006-10-01), 497-504 1087-6596 32:5<497 2006 32 10720 https://doi.org/10.1134/S1087659606050014 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1087659606050014 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sigaev V. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut NATIONALLICENCE 700 1- Lotarev S. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut NATIONALLICENCE 700 1- Smelyanskaya E. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut NATIONALLICENCE 700 1- Sarkisov P. Mendeleev University of Chemical Technology, Miusskaya pl. 9, 125130, Moscow, Russia aut NATIONALLICENCE 700 1- Volkov A. Institute of General Physics, Russian Academy of Sciences, Leninskii pr. 53, 117924, Moscow, Russia aut NATIONALLICENCE 700 1- Komandin G. Institute of General Physics, Russian Academy of Sciences, Leninskii pr. 53, 117924, Moscow, Russia aut NATIONALLICENCE 700 1- Koltashev V. Research Center of Fiber Optics, Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, 119991, Moscow, Russia aut NATIONALLICENCE 700 1- Plotnichenko V. Research Center of Fiber Optics, Institute of General Physics, Russian Academy of Sciences, ul. Vavilova 38, 119991, Moscow, Russia aut NATIONALLICENCE 773 0- Glass Physics and Chemistry Nauka/Interperiodica 32/5(2006-10-01), 497-504 1087-6596 32:5<497 2006 32 10720 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 467923124 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer