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Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite
The benefit of computational methods applying density functional theory for the description and understanding of modulated crystal structures is investigated. A method is presented which allows one to establish, improve and test superspace models including displacive and occupational modulation func...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
International Union of Crystallography
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6396396/ https://www.ncbi.nlm.nih.gov/pubmed/30821259 http://dx.doi.org/10.1107/S2053273319000846 |
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author | Klar, Paul Benjamin Etxebarria, Iñigo Madariaga, Gotzon |
author_facet | Klar, Paul Benjamin Etxebarria, Iñigo Madariaga, Gotzon |
author_sort | Klar, Paul Benjamin |
collection | PubMed |
description | The benefit of computational methods applying density functional theory for the description and understanding of modulated crystal structures is investigated. A method is presented which allows one to establish, improve and test superspace models including displacive and occupational modulation functions from first-principles calculations on commensurate structures. The total energies of different configurations allow one to distinguish stable and less stable structure models. The study is based on a series of geometrically optimized superstructures of mullite (Al(4+2x)Si(2−2x)O(10−x)) derived from the superspace group Pbam(α0½)0ss. Despite the disordered and structurally complex nature of mullite, the calculations on ordered superstructures are very useful for determining the ideal Al/Si ordering in mullite, extracting atomic modulation functions as well as understanding the SiO(2)–Al(2)O(3) phase diagram. The results are compared with experimentally established models which confirm the validity and utility of the presented method. |
format | Online Article Text |
id | pubmed-6396396 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | International Union of Crystallography |
record_format | MEDLINE/PubMed |
spelling | pubmed-63963962019-03-13 Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite Klar, Paul Benjamin Etxebarria, Iñigo Madariaga, Gotzon Acta Crystallogr A Found Adv Research Papers The benefit of computational methods applying density functional theory for the description and understanding of modulated crystal structures is investigated. A method is presented which allows one to establish, improve and test superspace models including displacive and occupational modulation functions from first-principles calculations on commensurate structures. The total energies of different configurations allow one to distinguish stable and less stable structure models. The study is based on a series of geometrically optimized superstructures of mullite (Al(4+2x)Si(2−2x)O(10−x)) derived from the superspace group Pbam(α0½)0ss. Despite the disordered and structurally complex nature of mullite, the calculations on ordered superstructures are very useful for determining the ideal Al/Si ordering in mullite, extracting atomic modulation functions as well as understanding the SiO(2)–Al(2)O(3) phase diagram. The results are compared with experimentally established models which confirm the validity and utility of the presented method. International Union of Crystallography 2019-02-12 /pmc/articles/PMC6396396/ /pubmed/30821259 http://dx.doi.org/10.1107/S2053273319000846 Text en © Paul Benjamin Klar et al. 2019 http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Research Papers Klar, Paul Benjamin Etxebarria, Iñigo Madariaga, Gotzon Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title | Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title_full | Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title_fullStr | Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title_full_unstemmed | Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title_short | Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
title_sort | characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite |
topic | Research Papers |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6396396/ https://www.ncbi.nlm.nih.gov/pubmed/30821259 http://dx.doi.org/10.1107/S2053273319000846 |
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