| Full text | |
| Author(s): |
Total Authors: 4
|
| Affiliation: | [1] Univ Fed Rio Grande do Sul, LAPMA, Inst Phys, IF UFRGS, Porto Alegre, RS - Brazil
[2] Univ Fed Sao Carlos, Dept Fis, Rod Washington Luis, Km 235, BR-13565905 Sao Carlos, SP - Brazil
[3] Univ Fed Sao Carlos, Ctr Res Technol & Educ Vitreous Mat CeRTEV, Sao Carlos, SP - Brazil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | Journal of Non-Crystalline Solids; v. 550, DEC 15 2020. |
| Web of Science Citations: | 0 |
| Abstract | |
A systematic study of crystallization of barium disilicate at high pressures and temperatures was undertaken. Two groups of samples were submitted to nucleation at 710 degrees C, and then submitted to a crystal growth at either 860 degrees C or 960 degrees C respectively. Both groups were heat treated at 1 atm, 2.5 GPa, 4 GPa, and 7.7 GPa. The diffraction results show that at atmospheric pressure, the phases formed are, monoclinic Ba6Si10O26, orthorhombic low-Ba2Si4O10, and monoclinic high-Ba2Si4O10 depending on the temperature treatment. In contrast, at 7.7 GPa orthorhombic BaSiO3, monoclinic phase Ba6Si10O26 and coesite formed when treated at 860 degrees C, whereas monoclinic Ba6Si10O26 is predominantly formed when treated at 960 degrees C. At 2.5 and 4 GPa orthorhombic lowBa(2)Si(4)O(10) formed when treated at 960 degrees C. The high frequency Raman modes are strongly affected by the different pressure and temperature treatments. The shifts and formations of distinct vibrations modes are discussed as function of pressure. (AU) | |
| 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 |
| 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 |