Tautomerism of Uracil Probed via Infrared Spectroscopy of Singly Hydrated Protonated Uracil
Author | |
Abstract |
Tautomerism of the nucleobase uracil is characterized in the gas phase through IR photodissociation spectroscopy of singly hydrated protonated uracil created with tandem mass spectrometric methods in a commercially available Fourier transform ion cyclotron resonance mass spectrometer. Protonated Uracil ions generated by electrospray ionization are re-solvated ill a low-pressure collision cell filled with a mixture of water vapor seeded in argon. Their structure is investigated by IR photodissociation spectroscopy in the NH and OH stretching region (2500-3800 cm(-1)) with a tabletop IR laser Source and in the 1000-2000 cm(-1) range with a free-electron laser. In both regions the IR photodissociation spectrum exhibits well-resolved spectral signatures that point to the presence of two different types of structure for monohydrated protonated uracil, which result from the two lowest-energy tautomers of uracil. Ab initio calculations confirm that no water-catalyzed tautomerization occurs during the re-solvation process, indicating that the two protonated forms of uracil directly originate from the electrospray process. |
Year of Publication |
2008
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Journal |
Journal of Physical Chemistry A
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Volume |
112
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Number |
48
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Number of Pages |
12393-12400
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Date Published |
Dec
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Type of Article |
Article
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ISBN Number |
1089-5639
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Accession Number |
ISI:000261218100014
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URL |
<Go to ISI>://000261218100014
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PId |
31f62777c857ad75a36c33665591884d
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Alternate Journal |
J. Phys. Chem. A
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Journal Article
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