Identifying and explaining vibrational modes of sanbornite (low-BaSi2O5) and Ba5Si8O21: A joint experimental and theoretical study

Autor(es)

Gomes, Eduardo O. ^[1] ; Moulton, Benjamin J. A. ^{[2, 3]} ; Cunha, Thiago R. ^{[2, 3]} ; Gracia, Lourdes ^{[1, 4]} ; Pizani, Paulo S. ^{[2, 3]} ; Andres, Juan ^[1]

Afiliação do(s) autor(es)

^[1] Univ Jaume 1, Dept Quim Fis & Analit, Castellon de La Plana 12071 - Spain

^[2] Univ Fed Sao Carlos, CERTEV Ctr Res Technol & Educ Vitreous Mat, Dept Mat Engn, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Fed Sao Carlos, Dept Fis, Rod Washington Luis, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[4] Univ Valencia UV, Dept Phys Chem, Burjassot 46100 - Spain

• Tipo de documento: Artigo Científico
• Fonte: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 248, MAR 5 2021.
• Citações Web of Science: 0

Resumo

We report here the analysis of vibrational properties of the sanbornite (low-BaSi2O5) and Ba5Si8O21 using theoretical and experimental approaches, as well as results of high temperature experiments up to 1100-1150 degrees C. The crystal parameters derived from Rietveld refinement and calculations show excellent agreement, within 4%, while the absolute mean difference between the theoretical and experimental results for the IR and Raman vibrational frequencies was <6 cm(-1). The temperature-dependent Raman study renders that both sanbornite and Ba5Si8O21 display specific Ba and Si sites and their Ba-O and Si-O bonds. In the case of the stretching modes assigned to specific Si sites, the frequency dependence on the Si-O bond length exhibited very strong correlations. Both phases showed that for a change of 0.01 angstrom, the vibrational mode shifted 10 +/- 2 cm(-1). These results are promising for using Raman spectroscopy to track in situ reactions under a wide variety of conditions, especially during crystallization. (C) 2020 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 19/12383-8 - Estudo de propriedades estruturais e vibracionais de materiais vítreos e vitrocerâmicos via espalhamento Raman em função da temperatura e de altas pressões hidrostáticas.
• Beneficiário: Thiago Rodrigues da Cunha
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 16/18567-5 - Ordenamento estrutural pré-nucleação em vidros que nucleiam homogeneamente: BaO-2SiO2 e CaO-SiO2
• Beneficiário: Benjamin John Albert Moulton
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros
• Beneficiário: Edgar Dutra Zanotto
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs