dc.creatorReis, AKCA
dc.creatorRittner, R
dc.date2007
dc.dateMAR
dc.date2014-11-14T09:55:07Z
dc.date2015-11-26T17:14:19Z
dc.date2014-11-14T09:55:07Z
dc.date2015-11-26T17:14:19Z
dc.date.accessioned2018-03-29T00:02:39Z
dc.date.available2018-03-29T00:02:39Z
dc.identifierSpectrochimica Acta Part A-molecular And Biomolecular Spectroscopy. Pergamon-elsevier Science Ltd, v. 66, n. 3, n. 681, n. 685, 2007.
dc.identifier1386-1425
dc.identifierWOS:000244850500026
dc.identifier10.1016/j.saa.2006.04.011
dc.identifierhttp://www.repositorio.unicamp.br/jspui/handle/REPOSIP/74675
dc.identifierhttp://www.repositorio.unicamp.br/handle/REPOSIP/74675
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/74675
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1281785
dc.descriptionC-13 chemical shifts empirical calculations, through a very simple additivity relationship, for the alpha-methylene carbon of some a-mono- substituted acetonitriles, Y-CH2-CN (Y = H, F, Cl, Br, I, OMe, OEt, SMe, SEt, NMe2, NEt2, Me and Et), lead to similar, or even better, results in comparison to the reported values obtained through Quantum Mechanics methods. The observed deviations, for some substituents, are very similar for both approaches. This divergence between experimental and calculated, either empirically or theoretically, values are smaller than for the corresponding acetones, amides, acetic acids and methyl esters, which had been named non-additivity effects (or intramolecular interaction chemical shifts, ICS) and attributed to some orbital interactions. Here, these orbital interactions do not seem to be the main reason for the non-additivity effects in the empirical calculations, which must be due solely to the magnetic anisotropy of the heavy atom present in the substituent. These deviations, which were also observed in the theoretical calculations, were attributed in that case to the non-inclusion of relativistic effects and spin-orbit coupling in the Hamiltonian. Some divergence is also observed for the cyano carbon chemical shifts, probably due to the same reasons. (c) 2006 Elsevier B.V. All rights reserved.
dc.description66
dc.description3
dc.description681
dc.description685
dc.languageen
dc.publisherPergamon-elsevier Science Ltd
dc.publisherOxford
dc.publisherInglaterra
dc.relationSpectrochimica Acta Part A-molecular And Biomolecular Spectroscopy
dc.relationSpectroc. Acta Pt. A-Molec. Biomolec. Spectr.
dc.rightsfechado
dc.rightshttp://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy
dc.sourceWeb of Science
dc.subjectNMR chemical shifts
dc.subjectempirical calculations
dc.subjectsubstituted acetonitriles
dc.subjectMagnetic-resonance
dc.subjectAliphatic Nitriles
dc.subjectElectronegativity
dc.subjectDependence
dc.subjectC13
dc.titleSubstituent effects in the C-13 NMR chemical shifts of alpha-mono-substituted acetonitriles
dc.typeArtículos de revistas


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