Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca
Autor(a) principal: | |
---|---|
Data de Publicação: | 2001 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | por |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://hdl.handle.net/11449/231728 |
Resumo: | Eu3+ luminescence and EXAFS (Extended X-ray Absorption Fine Structure) results are presented for organic-inorganic hybrid gel hosts composed of a siliceous network to which small chains of oxyethylene units are covalently grafted by means of urea bridges. Coordination numbers for Eu3+ ions range from 12.8 to 9.7 with increasing Eu3+ concentration while the Eu3+-first neighbours mean distance is found to be constant at 2.48-2.49 Å in the same concentration range. Emission spectra display a broad band in the green/blue spectral region superposed to narrow lines appearing in the yellow/red region in such a way that for the eyes emission appears white. The broad band is assigned to intrinsic NH groups emission and also to electron-hole recombination in the nanosised siliceous domains. The narrow lines are assigned to intra-4f6, 5D0→7F0-4 Eu3+ transitions and from the energy position of the 7F0-4 levels a mean distance could be calculated for the Eu3+-first neighbours. The calculated results are in good agreement with the experimental ones obtained from EXAFS analysis. |
id |
UNSP_4ca1766bb77ee0aafbfd7c39246167ef |
---|---|
oai_identifier_str |
oai:repositorio.unesp.br:11449/231728 |
network_acronym_str |
UNSP |
network_name_str |
Repositório Institucional da UNESP |
repository_id_str |
2946 |
spelling |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz brancaEu(III) local coordination in white light emitters organic-inorganic hybridsEXAFSLuminescenceOrganic-inorganic hybridsEu3+ luminescence and EXAFS (Extended X-ray Absorption Fine Structure) results are presented for organic-inorganic hybrid gel hosts composed of a siliceous network to which small chains of oxyethylene units are covalently grafted by means of urea bridges. Coordination numbers for Eu3+ ions range from 12.8 to 9.7 with increasing Eu3+ concentration while the Eu3+-first neighbours mean distance is found to be constant at 2.48-2.49 Å in the same concentration range. Emission spectra display a broad band in the green/blue spectral region superposed to narrow lines appearing in the yellow/red region in such a way that for the eyes emission appears white. The broad band is assigned to intrinsic NH groups emission and also to electron-hole recombination in the nanosised siliceous domains. The narrow lines are assigned to intra-4f6, 5D0→7F0-4 Eu3+ transitions and from the energy position of the 7F0-4 levels a mean distance could be calculated for the Eu3+-first neighbours. The calculated results are in good agreement with the experimental ones obtained from EXAFS analysis.Departamento de Física Universidade de Aveiro, 3810 AveiroDepto. de Química Univ. de Tras-os-Montes e Alto Douro, Quinta de Prados, Apartado 202, 5001 Vila Real CodexInstituto de Química UNESP, CP 355, 14801-970 Araraquara - SPInstituto de Química UNESP, CP 355, 14801-970 Araraquara - SPUniversidade de AveiroUniv. de Tras-os-Montes e Alto DouroUniversidade Estadual Paulista (UNESP)Carlos, Luís D.Sá Ferreira, Rute A.De Zéa Bermudez, VerónicaBueno, Luciano A. [UNESP]Molina, Celso [UNESP]Messaddeq, Younes [UNESP]Ribeiro, Sidney J. L. [UNESP]2022-04-29T08:47:14Z2022-04-29T08:47:14Z2001-07-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article453-459Quimica Nova, v. 24, n. 4, p. 453-459, 2001.0100-4042http://hdl.handle.net/11449/2317282-s2.0-0345856299Scopusreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPporQuimica Novainfo:eu-repo/semantics/openAccess2022-04-29T08:47:14Zoai:repositorio.unesp.br:11449/231728Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-08-05T17:02:17.692442Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca Eu(III) local coordination in white light emitters organic-inorganic hybrids |
title |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
spellingShingle |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca Carlos, Luís D. EXAFS Luminescence Organic-inorganic hybrids |
title_short |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
title_full |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
title_fullStr |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
title_full_unstemmed |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
title_sort |
Coordenaçāo local do Eu(III) em híbridos orgânicos/inorgânicos emissores de luz branca |
author |
Carlos, Luís D. |
author_facet |
Carlos, Luís D. Sá Ferreira, Rute A. De Zéa Bermudez, Verónica Bueno, Luciano A. [UNESP] Molina, Celso [UNESP] Messaddeq, Younes [UNESP] Ribeiro, Sidney J. L. [UNESP] |
author_role |
author |
author2 |
Sá Ferreira, Rute A. De Zéa Bermudez, Verónica Bueno, Luciano A. [UNESP] Molina, Celso [UNESP] Messaddeq, Younes [UNESP] Ribeiro, Sidney J. L. [UNESP] |
author2_role |
author author author author author author |
dc.contributor.none.fl_str_mv |
Universidade de Aveiro Univ. de Tras-os-Montes e Alto Douro Universidade Estadual Paulista (UNESP) |
dc.contributor.author.fl_str_mv |
Carlos, Luís D. Sá Ferreira, Rute A. De Zéa Bermudez, Verónica Bueno, Luciano A. [UNESP] Molina, Celso [UNESP] Messaddeq, Younes [UNESP] Ribeiro, Sidney J. L. [UNESP] |
dc.subject.por.fl_str_mv |
EXAFS Luminescence Organic-inorganic hybrids |
topic |
EXAFS Luminescence Organic-inorganic hybrids |
description |
Eu3+ luminescence and EXAFS (Extended X-ray Absorption Fine Structure) results are presented for organic-inorganic hybrid gel hosts composed of a siliceous network to which small chains of oxyethylene units are covalently grafted by means of urea bridges. Coordination numbers for Eu3+ ions range from 12.8 to 9.7 with increasing Eu3+ concentration while the Eu3+-first neighbours mean distance is found to be constant at 2.48-2.49 Å in the same concentration range. Emission spectra display a broad band in the green/blue spectral region superposed to narrow lines appearing in the yellow/red region in such a way that for the eyes emission appears white. The broad band is assigned to intrinsic NH groups emission and also to electron-hole recombination in the nanosised siliceous domains. The narrow lines are assigned to intra-4f6, 5D0→7F0-4 Eu3+ transitions and from the energy position of the 7F0-4 levels a mean distance could be calculated for the Eu3+-first neighbours. The calculated results are in good agreement with the experimental ones obtained from EXAFS analysis. |
publishDate |
2001 |
dc.date.none.fl_str_mv |
2001-07-01 2022-04-29T08:47:14Z 2022-04-29T08:47:14Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
Quimica Nova, v. 24, n. 4, p. 453-459, 2001. 0100-4042 http://hdl.handle.net/11449/231728 2-s2.0-0345856299 |
identifier_str_mv |
Quimica Nova, v. 24, n. 4, p. 453-459, 2001. 0100-4042 2-s2.0-0345856299 |
url |
http://hdl.handle.net/11449/231728 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.relation.none.fl_str_mv |
Quimica Nova |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
453-459 |
dc.source.none.fl_str_mv |
Scopus reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1808128743717208064 |