English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/65376
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:
DC FieldValueLanguage
dc.contributor.authorSenent, María Luisa-
dc.contributor.authorNiño, A.-
dc.contributor.authorMuñoz-Caro, C.-
dc.contributor.authorSmeyers, Y. G.-
dc.contributor.authorDomínguez Gómez, R.-
dc.contributor.authorOrza, J. M.-
dc.identifierdoi: 10.1021/jp026542f-
dc.identifierissn: 1089-5639-
dc.identifier.citationThe journal of physical chemistry, A, Molecules, spectroscopy, kinetics, environment & general theory 106: 10673-10680 (2002)-
dc.description.abstractThe structural and spectroscopic effects of hydrogen bonding on isolated 2,2,2-trifluoroethanol (TFE) and its molecular complexes are theoretically investigated at the MP2/aug-cc-pVDZ level. As a result, previous interpretations of the relative stability of the trans and gauche conformers of the isolated molecule are revised. We show that the prevalence of the gauche form is due to a decrease of repulsion forces, rather than to the formation of an intramolecular hydrogen bond. We find that the instability of the trans geometry is caused by repulsion forces between the oxygen electronic pair and the fluorine atom clouds, which are significantly stronger in trans-TFE. Molecular agents capable of weakening the repulsion produce stabilization. These results lead to a reinterpretation of the stabilizing factors of halogenated compounds. To analyze complexation, two small molecules (water and ammonia) have been chosen. Water can form four different molecular aggregates with TFE. The most stable corresponds to a species where H2O acts as hydrogen donor and TFE presents the cis-gauche conformation, forming two intramolecular hydrogen bonds. For NH3, the cis-gauche conformation loses stability, because of steric hindrance. In this case, TFE varies the relative stability of its conformers, with trans-TFE becoming the preferred structure. Hydrogen bond formation between NH3 and trans-TFE produces vibrational shifts of -354, -17, and +518 cm-1 for the OH stretching, the OH bending, and the OH torsion, in agreement with the experimental findings. We found complexation to produce an important variation of the position of the infrared bands corresponding to the hydroxyl group.-
dc.description.sponsorshipThis work has been supported by the “Ministerio de Ciencia y Tecnología” of Spain through grants no. BFM2000-1106 and AYA2002-02117. C.M. and A.N. thank the DGESIC (grant no. PM98-0073) for financial support.-
dc.publisherAmerican Chemical Society-
dc.titleTheoretical study of the effect of hydrogen-bonding on the stability and vibrational spectrum of isolated 2,2,2-trifluoroethanol and its molecular complexes-
dc.description.versionPeer Reviewed-
Appears in Collections:(CFMAC-IEM) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
Show simple item record

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.