Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings

Autores
Provasi, Patricio Federico; Gómez, Carlos Anselmo; Aucar, Gustavo Adolfo
Año de publicación
2004
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The electronic origin of the Karplus-type behavior of vicinal NMR J couplings for H3X−C2H4−XH3, X = C, Sn model compound is analyzed within the framework of the polarization propagator formalism. It is shown that its whole pattern can be understood by generalizing previous hyperconjugative mechanisms, in such a way that the hyperconjugative delocalization effect from an excitation σ → σ* should be replaced by two simultaneous excitations according to a second-order electronic property. All and the main coupling pathway which involve, at the random phase level of approach, RPA, the two pairs of localized MOs closest to the coupled nuclei follows a Karplus-type dependence with dihedral X−C−C−X angle, θ. The specific two-electron integrals which include correlation at RPA level of approach are the main factors which define the total behavior of J. The Karplus-type dependence is also found at HF level for individual coupling pathways though that is not observed for the total J; the so-called nonlocal “perturbators” together with the inverse of the differences of energies define, at this level of approach, the functional dependence with θ.
Fil: Provasi, Patricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
Fil: Gómez, Carlos Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
Fil: Aucar, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
Materia
Nmr
Spin-Spin Coupling Constant
Karplus Curve
Hyperconjugation
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/22023
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/22023
network_acronym_str CONICETDig
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network_name_str CONICET Digital (CONICET)
spelling Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplingsProvasi, Patricio FedericoGómez, Carlos AnselmoAucar, Gustavo AdolfoNmrSpin-Spin Coupling ConstantKarplus CurveHyperconjugationhttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1The electronic origin of the Karplus-type behavior of vicinal NMR J couplings for H3X−C2H4−XH3, X = C, Sn model compound is analyzed within the framework of the polarization propagator formalism. It is shown that its whole pattern can be understood by generalizing previous hyperconjugative mechanisms, in such a way that the hyperconjugative delocalization effect from an excitation σ → σ* should be replaced by two simultaneous excitations according to a second-order electronic property. All and the main coupling pathway which involve, at the random phase level of approach, RPA, the two pairs of localized MOs closest to the coupled nuclei follows a Karplus-type dependence with dihedral X−C−C−X angle, θ. The specific two-electron integrals which include correlation at RPA level of approach are the main factors which define the total behavior of J. The Karplus-type dependence is also found at HF level for individual coupling pathways though that is not observed for the total J; the so-called nonlocal “perturbators” together with the inverse of the differences of energies define, at this level of approach, the functional dependence with θ.Fil: Provasi, Patricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; ArgentinaFil: Gómez, Carlos Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; ArgentinaFil: Aucar, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; ArgentinaAmerican Chemical Society2004-06info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/22023Provasi, Patricio Federico; Gómez, Carlos Anselmo; Aucar, Gustavo Adolfo; Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings; American Chemical Society; Journal of Physical Chemistry A; 108; 29; 6-2004; 6231-62381089-5639CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1021/jp0369948info:eu-repo/semantics/altIdentifier/url/http://pubs.acs.org/doi/10.1021/jp0369948info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-10-22T11:36:33Zoai:ri.conicet.gov.ar:11336/22023instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-10-22 11:36:34.175CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
title Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
spellingShingle Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
Provasi, Patricio Federico
Nmr
Spin-Spin Coupling Constant
Karplus Curve
Hyperconjugation
title_short Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
title_full Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
title_fullStr Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
title_full_unstemmed Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
title_sort Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings
dc.creator.none.fl_str_mv Provasi, Patricio Federico
Gómez, Carlos Anselmo
Aucar, Gustavo Adolfo
author Provasi, Patricio Federico
author_facet Provasi, Patricio Federico
Gómez, Carlos Anselmo
Aucar, Gustavo Adolfo
author_role author
author2 Gómez, Carlos Anselmo
Aucar, Gustavo Adolfo
author2_role author
author
dc.subject.none.fl_str_mv Nmr
Spin-Spin Coupling Constant
Karplus Curve
Hyperconjugation
topic Nmr
Spin-Spin Coupling Constant
Karplus Curve
Hyperconjugation
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv The electronic origin of the Karplus-type behavior of vicinal NMR J couplings for H3X−C2H4−XH3, X = C, Sn model compound is analyzed within the framework of the polarization propagator formalism. It is shown that its whole pattern can be understood by generalizing previous hyperconjugative mechanisms, in such a way that the hyperconjugative delocalization effect from an excitation σ → σ* should be replaced by two simultaneous excitations according to a second-order electronic property. All and the main coupling pathway which involve, at the random phase level of approach, RPA, the two pairs of localized MOs closest to the coupled nuclei follows a Karplus-type dependence with dihedral X−C−C−X angle, θ. The specific two-electron integrals which include correlation at RPA level of approach are the main factors which define the total behavior of J. The Karplus-type dependence is also found at HF level for individual coupling pathways though that is not observed for the total J; the so-called nonlocal “perturbators” together with the inverse of the differences of energies define, at this level of approach, the functional dependence with θ.
Fil: Provasi, Patricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
Fil: Gómez, Carlos Anselmo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
Fil: Aucar, Gustavo Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura. Departamento de Física; Argentina
description The electronic origin of the Karplus-type behavior of vicinal NMR J couplings for H3X−C2H4−XH3, X = C, Sn model compound is analyzed within the framework of the polarization propagator formalism. It is shown that its whole pattern can be understood by generalizing previous hyperconjugative mechanisms, in such a way that the hyperconjugative delocalization effect from an excitation σ → σ* should be replaced by two simultaneous excitations according to a second-order electronic property. All and the main coupling pathway which involve, at the random phase level of approach, RPA, the two pairs of localized MOs closest to the coupled nuclei follows a Karplus-type dependence with dihedral X−C−C−X angle, θ. The specific two-electron integrals which include correlation at RPA level of approach are the main factors which define the total behavior of J. The Karplus-type dependence is also found at HF level for individual coupling pathways though that is not observed for the total J; the so-called nonlocal “perturbators” together with the inverse of the differences of energies define, at this level of approach, the functional dependence with θ.
publishDate 2004
dc.date.none.fl_str_mv 2004-06
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/22023
Provasi, Patricio Federico; Gómez, Carlos Anselmo; Aucar, Gustavo Adolfo; Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings; American Chemical Society; Journal of Physical Chemistry A; 108; 29; 6-2004; 6231-6238
1089-5639
CONICET Digital
CONICET
url http://hdl.handle.net/11336/22023
identifier_str_mv Provasi, Patricio Federico; Gómez, Carlos Anselmo; Aucar, Gustavo Adolfo; Hyperconjugation: the electronic mechanism that may underlie the Karplus curve of vicinal NMR indirect spin couplings; American Chemical Society; Journal of Physical Chemistry A; 108; 29; 6-2004; 6231-6238
1089-5639
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1021/jp0369948
info:eu-repo/semantics/altIdentifier/url/http://pubs.acs.org/doi/10.1021/jp0369948
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv American Chemical Society
publisher.none.fl_str_mv American Chemical Society
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 12.982451

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