Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6)
Autor(a) principal: | |
---|---|
Data de Publicação: | 2006 |
Outros Autores: | , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10316/10392 https://doi.org/10.1021/jp055455v |
Resumo: | The photophysics of six oligothiophenes end-capped with cyano groups (CNαn) was investigated in solution at room and low temperature. The study comprises singlet−singlet and triplet−triplet absorption and emission spectra together with lifetimes and quantum yields for all the radiative and nonradiative processes. From the lifetimes and quantum yields, it was possible to extract the rate constants for all the processes. Singlet oxygen yields were also determined, revealing an efficient sensitization (SΔ ≈ 1) of its formation by the triplet state of the CNαn. The introduction of the cyano groups is found to decrease the energetic separation between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, leading to a red shift of the absorption and the emission when compared with the unsubstituted counterparts, the α-oligothiophenes. Phosphorescence is only observed for the first member of the series, CNα1. |
id |
RCAP_d2417fcb043a4103962b3acc03f724b0 |
---|---|
oai_identifier_str |
oai:estudogeral.uc.pt:10316/10392 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6)The photophysics of six oligothiophenes end-capped with cyano groups (CNαn) was investigated in solution at room and low temperature. The study comprises singlet−singlet and triplet−triplet absorption and emission spectra together with lifetimes and quantum yields for all the radiative and nonradiative processes. From the lifetimes and quantum yields, it was possible to extract the rate constants for all the processes. Singlet oxygen yields were also determined, revealing an efficient sensitization (SΔ ≈ 1) of its formation by the triplet state of the CNαn. The introduction of the cyano groups is found to decrease the energetic separation between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, leading to a red shift of the absorption and the emission when compared with the unsubstituted counterparts, the α-oligothiophenes. Phosphorescence is only observed for the first member of the series, CNα1.American Chemical Society2006-03-06info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10316/10392http://hdl.handle.net/10316/10392https://doi.org/10.1021/jp055455vengThe Journal of Physical Chemistry B. 110:13 (2006) 6499-65051520-6106Pina, J.Burrows, H. D.Becker, R. S.Dias, F. B.Maçanita, A. L.Melo, J. Seixas deinfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2021-09-22T11:00:52Zoai:estudogeral.uc.pt:10316/10392Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:01:15.681808Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
title |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
spellingShingle |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) Pina, J. |
title_short |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
title_full |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
title_fullStr |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
title_full_unstemmed |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
title_sort |
Photophysical Studies of α,ω-Dicyano-oligothiophenes NC(C4H2S)nCN (n = 1−6) |
author |
Pina, J. |
author_facet |
Pina, J. Burrows, H. D. Becker, R. S. Dias, F. B. Maçanita, A. L. Melo, J. Seixas de |
author_role |
author |
author2 |
Burrows, H. D. Becker, R. S. Dias, F. B. Maçanita, A. L. Melo, J. Seixas de |
author2_role |
author author author author author |
dc.contributor.author.fl_str_mv |
Pina, J. Burrows, H. D. Becker, R. S. Dias, F. B. Maçanita, A. L. Melo, J. Seixas de |
description |
The photophysics of six oligothiophenes end-capped with cyano groups (CNαn) was investigated in solution at room and low temperature. The study comprises singlet−singlet and triplet−triplet absorption and emission spectra together with lifetimes and quantum yields for all the radiative and nonradiative processes. From the lifetimes and quantum yields, it was possible to extract the rate constants for all the processes. Singlet oxygen yields were also determined, revealing an efficient sensitization (SΔ ≈ 1) of its formation by the triplet state of the CNαn. The introduction of the cyano groups is found to decrease the energetic separation between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, leading to a red shift of the absorption and the emission when compared with the unsubstituted counterparts, the α-oligothiophenes. Phosphorescence is only observed for the first member of the series, CNα1. |
publishDate |
2006 |
dc.date.none.fl_str_mv |
2006-03-06 |
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 |
http://hdl.handle.net/10316/10392 http://hdl.handle.net/10316/10392 https://doi.org/10.1021/jp055455v |
url |
http://hdl.handle.net/10316/10392 https://doi.org/10.1021/jp055455v |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
The Journal of Physical Chemistry B. 110:13 (2006) 6499-6505 1520-6106 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
American Chemical Society |
publisher.none.fl_str_mv |
American Chemical Society |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799133904807919616 |