Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon
Autor(a) principal: | |
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Data de Publicação: | 2004 |
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/10316/17877 https://doi.org/10.1021/jp037840v |
Resumo: | Acetic acid monomer has two stable geometries, the cis and trans conformers. The high-energy cis conformer has been recently detected experimentally for the first time [Maçôas et al. J. Am. Chem. Soc. 2003, 125, 16188]. The cis conformer can be produced in low-temperature rare-gas matrixes upon vibrational excitation of the ground-state trans conformer. Fast tunneling from cis- to trans-acetic acid takes place even at the lowest working temperatures (8 K), limiting the time available to study the high-energy form. Deuteration of the hydroxyl group reduces the tunneling rate by approximately 4 orders of magnitude, increasing accordingly the lifetime of the unstable conformer and its available concentration. In this work, we present a detailed analysis of the vibrational spectra of the cis form of four acetic acid isotopologues (CH3COOH, CH3COOD, CD3COOH and CD3COOD). Photolysis (193 nm) of the trans and cis forms of the perdeuterated compound was performed to evaluate the possible conformational dependence of photodissociation of acetic acid. However, no evidence of conformer specific photodissociation was found. The UV photolysis of the matrix-isolated acetic acid reveals very different products from the gas phase. Methanol complexed with carbon monoxide is the major product of photolysis of acetic acid isolated in Ar matrixes whereas it has never been observed as a photolysis product in the gas phase. |
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Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid ArgonAcetic acid monomer has two stable geometries, the cis and trans conformers. The high-energy cis conformer has been recently detected experimentally for the first time [Maçôas et al. J. Am. Chem. Soc. 2003, 125, 16188]. The cis conformer can be produced in low-temperature rare-gas matrixes upon vibrational excitation of the ground-state trans conformer. Fast tunneling from cis- to trans-acetic acid takes place even at the lowest working temperatures (8 K), limiting the time available to study the high-energy form. Deuteration of the hydroxyl group reduces the tunneling rate by approximately 4 orders of magnitude, increasing accordingly the lifetime of the unstable conformer and its available concentration. In this work, we present a detailed analysis of the vibrational spectra of the cis form of four acetic acid isotopologues (CH3COOH, CH3COOD, CD3COOH and CD3COOD). Photolysis (193 nm) of the trans and cis forms of the perdeuterated compound was performed to evaluate the possible conformational dependence of photodissociation of acetic acid. However, no evidence of conformer specific photodissociation was found. The UV photolysis of the matrix-isolated acetic acid reveals very different products from the gas phase. Methanol complexed with carbon monoxide is the major product of photolysis of acetic acid isolated in Ar matrixes whereas it has never been observed as a photolysis product in the gas phase.American Chemical Society2004-03info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10316/17877http://hdl.handle.net/10316/17877https://doi.org/10.1021/jp037840vengMaçôas, E. M. S.Khriachtchev, L.Fausto, R.Räsänen, M.info: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:RCAAP2021-10-15T13:01:20Zoai:estudogeral.uc.pt:10316/17877Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T21:01:44.499907Repositório 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 |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
title |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
spellingShingle |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon Maçôas, E. M. S. |
title_short |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
title_full |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
title_fullStr |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
title_full_unstemmed |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
title_sort |
Photochemistry and Vibrational Spectroscopy of the Trans and Cis Conformers of Acetic Acid in Solid Argon |
author |
Maçôas, E. M. S. |
author_facet |
Maçôas, E. M. S. Khriachtchev, L. Fausto, R. Räsänen, M. |
author_role |
author |
author2 |
Khriachtchev, L. Fausto, R. Räsänen, M. |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Maçôas, E. M. S. Khriachtchev, L. Fausto, R. Räsänen, M. |
description |
Acetic acid monomer has two stable geometries, the cis and trans conformers. The high-energy cis conformer has been recently detected experimentally for the first time [Maçôas et al. J. Am. Chem. Soc. 2003, 125, 16188]. The cis conformer can be produced in low-temperature rare-gas matrixes upon vibrational excitation of the ground-state trans conformer. Fast tunneling from cis- to trans-acetic acid takes place even at the lowest working temperatures (8 K), limiting the time available to study the high-energy form. Deuteration of the hydroxyl group reduces the tunneling rate by approximately 4 orders of magnitude, increasing accordingly the lifetime of the unstable conformer and its available concentration. In this work, we present a detailed analysis of the vibrational spectra of the cis form of four acetic acid isotopologues (CH3COOH, CH3COOD, CD3COOH and CD3COOD). Photolysis (193 nm) of the trans and cis forms of the perdeuterated compound was performed to evaluate the possible conformational dependence of photodissociation of acetic acid. However, no evidence of conformer specific photodissociation was found. The UV photolysis of the matrix-isolated acetic acid reveals very different products from the gas phase. Methanol complexed with carbon monoxide is the major product of photolysis of acetic acid isolated in Ar matrixes whereas it has never been observed as a photolysis product in the gas phase. |
publishDate |
2004 |
dc.date.none.fl_str_mv |
2004-03 |
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/10316/17877 http://hdl.handle.net/10316/17877 https://doi.org/10.1021/jp037840v |
url |
http://hdl.handle.net/10316/17877 https://doi.org/10.1021/jp037840v |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
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 |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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1799133907913801728 |