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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Structural Study of the Germanium-Aluminum-Borate Glasses by Solid State NMR and Raman Spectroscopies

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Franco, Douglas F. [1] ; Fernandes, Roger Gomes [1] ; Santagneli, Silvia Helena [1] ; de Oliveira Jr, Marcos ; Eckert, Hellmut [2, 3] ; Nalin, Marcelo [1]
Total Authors: 6
[1] Sao Paulo State Univ, UNESP, Inst Chem, Araraquara, SP - Brazil
[2] de Oliveira Jr, Jr., Marcos, Univ Sao Paulo, USP, Sao Carlos Inst Phys, Sao Carlos, SP - Brazil
[3] Westfalische Wilhelms Univ, Inst Phys Chem, D-48149 Munster - Germany
Total Affiliations: 3
Document type: Journal article
Source: Journal of Physical Chemistry C; v. 124, n. 44, SI, p. 24460-24469, NOV 5 2020.
Web of Science Citations: 0

Glasses in the system (85-x)GeO2-(x)B2O3-10Na(2)O-4Al(2)O(3)-1PbO, which are used as matrices for rare-earth ion containing magneto-optic glasses have been prepared and their thermal and structural properties have been characterized by differential scanning calorimetry, Raman scattering, and solid state NMR spectroscopies. Besides showing the features of the corresponding borogermanate binary glasses, the Raman spectra also reveal new features consistent with the occurrence of B-O-Ge connectivities. One- and two-dimensional Na-23, Al-27, and B-11 NMR spectra reveal monotonic structural changes as a function of composition, reflecting the competition of the three network former species for charge compensation by the network modifier cations. Aluminum is found in a predominantly four-coordinated environment. Its anionic functionalization and, with second priority, that of the boron oxide component take precedence over that of the germanium oxide component. The glass transition temperature decreases with increasing B2O3 content and shows an excellent correlation with the average network connectivity deduced from the NMR data. (AU)

FAPESP's process: 18/24735-3 - The correlation between structure and properties as investigated by multinuclear solid state NMR in disordered materials
Grantee:Silvia Helena Santagneli
Support type: Regular Research Grants
FAPESP's process: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass
Grantee:Edgar Dutra Zanotto
Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC