Speciation and polymerization in a barium silicate glass: Evidence from Si-29 NMR and Raman spectroscopies

Author(s)

Moulton, Benjamin J. A. ^{[1, 2]} ; Silva, Lais D. ^[1] ; Doerenkamp, Carsten ^[3] ; Lozano, Harold ^[3] ; Zanotto, Edgar D. ^[1] ; Eckert, Hellmut ^{[4, 1, 3]} ; Pizani, Paulo S. ^{[1, 2]}

Affiliation

^[1] Univ Fed Sao Carlos, Dept Mat Engn, CERTEV Ctr Res Technol & Educ Vitreous Mat, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Fis, Rod Washington Luis, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Sao Paulo, Inst Phys Sao Carlos, Ave Trabalhador Sao Carlense 400, BR-13566590 Sao Carlos, SP - Brazil

^[4] Westfalische Wilhelms Univ Munster, Inst Phys Chem, Corrensstr 28-30, D-48149 Munster - Germany

• Document type: Journal article
• Source: CHEMICAL GEOLOGY; v. 586, DEC 30 2021.
• Web of Science Citations: 0

Abstract

Raman and NMR spectroscopies have long been employed in pursuing quantitative relationships between polymerization of silicate glasses and melts. However, varying assumptions and ambiguities have often meant structural models vary significantly depending on the probe used. This study investigates a 40BaO center dot 60SiO(2) glass to determine its polymerization using static and MAS Si-29 NMR, and Raman spectroscopies to construct a coherent structural interpretation. The challenges and advantages of each technique are discussed as the structural model of 40BaO-60SiO(2) glass required partial evidence derived from each of these spectroscopies. The Raman scattering cross sections for Q(2) and Q(3) were found to be 0.85 and 1.22, respectively. The Q(n) distribution was shown to be 3, 35, 57, 6% (+/- 4%) for Q(1) to Q(4), respectively. This distribution yields a polymerization consistent with the stoichiometry, Ba0.66SiO2.66, having a O:Si ratio of 2.66. The agreement between all Q(n) distributions, the composition, the polymerization, and equilibrium constants strongly indicate that this structural interpretation is robust. (AU)

• FAPESP's process: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass
• Grantee: Edgar Dutra Zanotto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/06649-0 - New Optical Materials based on Rare-Earth Doped Oxyfluoride Glasses and Ceramics: Structural Studies by Electron Paramagnetic Resonance Methods
• Grantee: Carsten Doerenkamp
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/18567-5 - Nuclei entrapment: the pre-nucleation structural ordering of homogeneous nucleating BaO-2SiO2 and CaO-SiO2 glasses
• Grantee: Benjamin John Albert Moulton
• Support Opportunities: Scholarships in Brazil - Post-Doctoral