Influence of cage confinement on the photochemistry of matrix-isolated E‑β-Ionone : FT-IR and DFT study

2013
journal article
article
8
cris.lastimport.wos2024-04-10T03:16:12Z
dc.abstract.enβ -ionone, a model compound of carotenoids ring structure, was investigated by FT-IR spectroscopy in a low-temperature argon matrix as well as using B3LYP/6-311+ +G(d,p) and MP2/6-311++G(d,p) quantum-chemical calcu- lations. The spectrum of matrix-isolated E - β -ionone was analyzed and attributed to six conformers of the compound. Then, matrix-isolated E - β -ionone was submitted to UV irradiation using either a broadband source (with di ff erent cuto fffi lters) or a narrowband laser/MOPO system (at various wavelengths). Upon 240 nm narrowband irradiation, the formation of both Z - retro - γ -ionone and Z - β -ionone was observed, the reactant and the photoproducts being in a photostationary equilibrium. Under these conditions, the matrix environment was found to hamper subsequent reactions of Z - retro - γ -ionone and Z - β -ionone, so that this last species could be observed directly for the fi rst time. Furthermore, the formation of Z - retro - γ -ionone was shown to occur directly via an intramolecular [1,5] H-atom shift and thereby, under the constraints imposed by the matrix con fi nement, the conformations assumed by this photoproduct were found to be strictly determined by those initially assumed by the reactant molecules. Broadband irradiation resulted in the completion of the reaction (disappearance of the reactant) and the sole observation of Z - retro - γ -ionone. These results imply that under these conditions the Z - β -ionone is unstable, very likely decaying to additional conformers of Z - retro - γ -ionone, as re fl ected in the broader bands due to this photoproduct observed in the infrared spectra of the broadband irradiated matrix.pl
dc.affiliationWydział Chemii : Zakład Fizyki Chemicznejpl
dc.contributor.authorKaczor, Agnieszka - 128583 pl
dc.contributor.authorReva, I.pl
dc.contributor.authorFausto, R.pl
dc.date.accessioned2015-06-09T05:59:19Z
dc.date.available2015-06-09T05:59:19Z
dc.date.issued2013pl
dc.description.number5pl
dc.description.physical888-897pl
dc.description.volume117pl
dc.identifier.doi10.1021/jp310764upl
dc.identifier.eissn1520-5215pl
dc.identifier.issn1089-5639pl
dc.identifier.urihttp://ruj.uj.edu.pl/xmlui/handle/item/9039
dc.languageengpl
dc.language.containerengpl
dc.rights.licencebez licencji
dc.subtypeArticlepl
dc.titleInfluence of cage confinement on the photochemistry of matrix-isolated E‑β-Ionone : FT-IR and DFT studypl
dc.title.journalThe Journal of Physical Chemistry. Apl
dc.typeJournalArticlepl
dspace.entity.typePublication
cris.lastimport.wos
2024-04-10T03:16:12Z
dc.abstract.enpl
β -ionone, a model compound of carotenoids ring structure, was investigated by FT-IR spectroscopy in a low-temperature argon matrix as well as using B3LYP/6-311+ +G(d,p) and MP2/6-311++G(d,p) quantum-chemical calcu- lations. The spectrum of matrix-isolated E - β -ionone was analyzed and attributed to six conformers of the compound. Then, matrix-isolated E - β -ionone was submitted to UV irradiation using either a broadband source (with di ff erent cuto fffi lters) or a narrowband laser/MOPO system (at various wavelengths). Upon 240 nm narrowband irradiation, the formation of both Z - retro - γ -ionone and Z - β -ionone was observed, the reactant and the photoproducts being in a photostationary equilibrium. Under these conditions, the matrix environment was found to hamper subsequent reactions of Z - retro - γ -ionone and Z - β -ionone, so that this last species could be observed directly for the fi rst time. Furthermore, the formation of Z - retro - γ -ionone was shown to occur directly via an intramolecular [1,5] H-atom shift and thereby, under the constraints imposed by the matrix con fi nement, the conformations assumed by this photoproduct were found to be strictly determined by those initially assumed by the reactant molecules. Broadband irradiation resulted in the completion of the reaction (disappearance of the reactant) and the sole observation of Z - retro - γ -ionone. These results imply that under these conditions the Z - β -ionone is unstable, very likely decaying to additional conformers of Z - retro - γ -ionone, as re fl ected in the broader bands due to this photoproduct observed in the infrared spectra of the broadband irradiated matrix.
dc.affiliationpl
Wydział Chemii : Zakład Fizyki Chemicznej
dc.contributor.authorpl
Kaczor, Agnieszka - 128583
dc.contributor.authorpl
Reva, I.
dc.contributor.authorpl
Fausto, R.
dc.date.accessioned
2015-06-09T05:59:19Z
dc.date.available
2015-06-09T05:59:19Z
dc.date.issuedpl
2013
dc.description.numberpl
5
dc.description.physicalpl
888-897
dc.description.volumepl
117
dc.identifier.doipl
10.1021/jp310764u
dc.identifier.eissnpl
1520-5215
dc.identifier.issnpl
1089-5639
dc.identifier.uri
http://ruj.uj.edu.pl/xmlui/handle/item/9039
dc.languagepl
eng
dc.language.containerpl
eng
dc.rights.licence
bez licencji
dc.subtypepl
Article
dc.titlepl
Influence of cage confinement on the photochemistry of matrix-isolated E‑β-Ionone : FT-IR and DFT study
dc.title.journalpl
The Journal of Physical Chemistry. A
dc.typepl
JournalArticle
dspace.entity.type
Publication

* The migration of download and view statistics prior to the date of April 8, 2024 is in progress.

Views
3
Views per month
Views per city
Ashburn
1
Shanghai
1

No access

No Thumbnail Available