Source:http://linkedlifedata.com/resource/pubmed/id/19348486
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
16
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| pubmed:dateCreated |
2009-4-22
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| pubmed:abstractText |
1,2-Dihydronaphthalene (DHN) has been studied by matrix isolation infrared absorption spectroscopy, multiphoton infrared photodissociation (IRMPD) action spectroscopy, and density functional theory calculations. Formed by electrospray ionization, protonated 1,2-dihydronapthalene was injected into a Fourier transform ion cyclotron resonance mass spectrometer coupled to an infrared-tunable free electron laser and its IRMPD spectrum recorded. Multiphoton infrared irradiation of the protonated parent (m/z 131) yields two dissociation products, one with m/z 129 and the other with m/z 91. Results from density functional theory calculations (B3LYP/6-31++G(d,p)) were compared to the low-temperature matrix isolation infrared spectrum of neutral DHN, with excellent results. Calculations reveal that the most probable site of protonation is the 3-position, producing the trihydronaphthalene (THN) cation, 1,2,3-THN(+). The observed IRMPD spectrum of vapor-phase protonated parent matches well with that computed for 1,2,3-THN(+). Extensive B3LYP/6-31G(d,p) calculations of the potential energy surface of 1,2,3-THN(+) have been performed and provide insight into the mechanism of the two-channel photodissociation. These results provide support for a new model of the formation of H(2) in the interstellar medium. This model involves hydrogenation of a PAH cation to produce one or more aliphatic hydrogen-bearing carbons on the PAH framework, followed by photolytic formation and ejection of H(2).
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
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| pubmed:month |
Apr
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| pubmed:issn |
1520-5126
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| pubmed:author | |
| pubmed:issnType |
Electronic
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| pubmed:day |
29
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| pubmed:volume |
131
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
5784-91
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| pubmed:year |
2009
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| pubmed:articleTitle |
H(2) ejection from polycyclic aromatic hydrocarbons: infrared multiphoton dissociation study of protonated 1,2-dihydronaphthalene.
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| pubmed:affiliation |
Department of Chemistry and Center for Chemical Physics, P.O. Box 117200, University of Florida, Gainesville, Florida 32611-7200, USA. mvala@chem.ufl.edu
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| pubmed:publicationType |
Journal Article
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