Titelangaben
Ganisetti, Sudheer ; Gaddam, Anuraag ; Kumar, Rajesh ; Balaji, Sathravada ; Mather, Glenn C. ; Pascual, Maria J. ; Fabian, Margit ; Siegel, Renée ; Senker, Jürgen ; Kharton, Vladislav V. ; Guénolé, Julien ; Krishnan, N. M. Anoop ; Ferreira, José M. F. ; Allu, Amarnath R.:
Elucidating the formation of Al-NBO bonds, Al-O-Al linkages and clusters in alkaline-earth aluminosilicate glasses based on molecular dynamics simulations.
In: Physical Chemistry Chemical Physics.
Bd. 21
(2019)
Heft 43
.
- S. 23966-23977.
ISSN 1463-9084
DOI: https://doi.org/10.1039/c9cp04332b
Abstract
Exploring the reasons for the initiation of Al-O-Al bond formation in alkali-earth alumino silicate glasses is a key topic in the glass-science community. Evidence for the formation of Al-O-Al and Al-NBO bonds in the glass composition 38.7CaO-9.7MgO-12.9Al(2)O(3)-38.7SiO(2) (CMAS, mol%) has been provided based on Molecular Dynamics (MD) simulations. Analyses in the short-range order confirm that silicon and the majority of aluminium cations form regular tetrahedra. Well-separated homonuclear (Si-O-Si) and heteronuclear (Si-O-Al) cluster regions have been identified. In addition, a channel region (C-Region), separated from the network region, enriched with both NBO and non-framework modifier cations, has also been identified. These findings are in support of the previously proposed extended modified random network (EMRN) model for aluminosilicate glasses. A detailed analysis of the structural distributions revealed that a majority of Al, 51.6%, is found in Si-O-Al links. Although the formation of Al-O-Al and Al-NBO bonds is energetically less favourable, a significant amount of Al is found in Al-O-Al links (33.5%), violating Lowenstein's rule, and the remainder is bonded with non-bridging oxygen (NBO) in the form of Al-NBO (Al-O-(Ca, Mg)). The conditions necessary for the formation of less favourable bonds are attributed to the presence of a high amount of modifier cations in current CMAS glass and their preferable coordination.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | ISI:000496151800014 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Anorganische Chemie III Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Chemie > Lehrstuhl Anorganische Chemie III > Lehrstuhl Anorganische Chemie III - Univ.-Prof. Dr. Jürgen Senker Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik 500 Naturwissenschaften und Mathematik > 540 Chemie |
Eingestellt am: | 28 Mai 2020 09:04 |
Letzte Änderung: | 26 Aug 2022 06:20 |
URI: | https://eref.uni-bayreuth.de/id/eprint/55269 |