Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Y3Al5O12-SiO2 glasses: Structure and polyamorphism
Δημιουργός/Συγγραφέας:	Nasikas N.K. Retsinas A. Papatheodorou G.N.
Εκδότης:	Blackwell Publishing Inc.
Ημερομηνία:	2014
Γλώσσα:	Αγγλικά
ISSN:	0002-7820
DOI:	10.1111/jace.12999
Περίληψη:	Aerodynamic levitation and CO2 laser melting have been used to synthesize the yttrium aluminosilicate glasses zY2O 3-yAl2O3-xSiO2 with z/y = 3/5 corresponding to the YAG (Y3Al5O12) composition and x between ~5 and ~45 mol%. The low- And high-density (LDA inclusion and HDA matrix) polyamorphic phases in glasses with less than ~14 mol% SiO2 were identified with backscattering electron imaging. Polarized and depolarized Raman spectra show the formation of various Qn SiO4 species whose relative populations change smoothly as the SiO2 content is altered. The AlOs (s = 4-6) and YOz (z = 6-9) polyhedra formed in the YAG glass are preserved upon silica additions while the terminal oxygens of the Q2AlO4 tetrahedra are gradually bridged to the Q n-SiO4 species. The low-frequency Boson Peak overlaps with the vibrational spectrum and its maximum is redshifted with increasing silica content. Micro-Raman spectra measured for the LDA and HDA amorphous phases are found to be similar to the spectra of the bulk glass indicating common structural characteristics. The stability of the LDA phase against crystallization appears to be lower than that of the HDA phase. The crystallinity on certain inclusions consisted of YAG microcrystals and a new unidentified microcrystalline phase within Y4Al 2(1-x)Si2xO(9+x) solid solution.
Τίτλος πηγής δημοσίευσης:	Journal of the American Ceramic Society
Τόμος/Κεφάλαιο:	97
Τεύχος:	7
Σελίδες:	2054-2060
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry
Αξιολόγηση από ομότιμους (peer reviewed):	Ναι
Κάτοχος πνευματικών δικαιωμάτων:	© 2014 The American Ceramic Society.
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο