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Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons
The standard D-G-2D pattern of Raman spectra of sp(2) amorphous carbons is considered from the viewpoint of graphene domains presenting their basic structure units (BSUs) in terms of molecular spectroscopy. The molecular approximation allows connecting the characteristic D-G doublet spectra image of...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7602257/ https://www.ncbi.nlm.nih.gov/pubmed/33066381 http://dx.doi.org/10.3390/nano10102021 |
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author | Sheka, Elena F. Golubev, Yevgeny A. Popova, Nadezhda A. |
author_facet | Sheka, Elena F. Golubev, Yevgeny A. Popova, Nadezhda A. |
author_sort | Sheka, Elena F. |
collection | PubMed |
description | The standard D-G-2D pattern of Raman spectra of sp(2) amorphous carbons is considered from the viewpoint of graphene domains presenting their basic structure units (BSUs) in terms of molecular spectroscopy. The molecular approximation allows connecting the characteristic D-G doublet spectra image of one-phonon spectra with a considerable dispersion of the C=C bond lengths within graphene domains, governed by size, heteroatom necklace of BSUs as well as BSUs packing. The interpretation of 2D two-phonon spectra reveals a particular role of electrical anharmonicity in the spectra formation and attributes this effect to a high degree of the electron density delocalization in graphene domains. A size-stimulated transition from molecular to quasi-particle phonon consideration of Raman spectra was experimentally traced, which allowed evaluation of a free path of optical phonons in graphene crystal. |
format | Online Article Text |
id | pubmed-7602257 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-76022572020-11-01 Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons Sheka, Elena F. Golubev, Yevgeny A. Popova, Nadezhda A. Nanomaterials (Basel) Article The standard D-G-2D pattern of Raman spectra of sp(2) amorphous carbons is considered from the viewpoint of graphene domains presenting their basic structure units (BSUs) in terms of molecular spectroscopy. The molecular approximation allows connecting the characteristic D-G doublet spectra image of one-phonon spectra with a considerable dispersion of the C=C bond lengths within graphene domains, governed by size, heteroatom necklace of BSUs as well as BSUs packing. The interpretation of 2D two-phonon spectra reveals a particular role of electrical anharmonicity in the spectra formation and attributes this effect to a high degree of the electron density delocalization in graphene domains. A size-stimulated transition from molecular to quasi-particle phonon consideration of Raman spectra was experimentally traced, which allowed evaluation of a free path of optical phonons in graphene crystal. MDPI 2020-10-14 /pmc/articles/PMC7602257/ /pubmed/33066381 http://dx.doi.org/10.3390/nano10102021 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Sheka, Elena F. Golubev, Yevgeny A. Popova, Nadezhda A. Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title | Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title_full | Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title_fullStr | Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title_full_unstemmed | Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title_short | Graphene Domain Signature of Raman Spectra of sp(2) Amorphous Carbons |
title_sort | graphene domain signature of raman spectra of sp(2) amorphous carbons |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7602257/ https://www.ncbi.nlm.nih.gov/pubmed/33066381 http://dx.doi.org/10.3390/nano10102021 |
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