Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework

One of the most influential articles showing the best way to get the absolute values of NMR magnetic shieldings, σ (non-measurables) from both accurate measurements and theoretical calculations, was published a long time ago by Flygare. His model was shown to break down when heavy atoms are involved...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Giribet, Claudia Gloria, Aucar, Gustavo A.
Publicado: 2016
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v18_n34_p23572_Aucar
http://hdl.handle.net/20.500.12110/paper_14639076_v18_n34_p23572_Aucar
Aporte de:
id paper:paper_14639076_v18_n34_p23572_Aucar
record_format dspace
spelling paper:paper_14639076_v18_n34_p23572_Aucar2023-06-08T16:16:29Z Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework Giribet, Claudia Gloria Aucar, Gustavo A. One of the most influential articles showing the best way to get the absolute values of NMR magnetic shieldings, σ (non-measurables) from both accurate measurements and theoretical calculations, was published a long time ago by Flygare. His model was shown to break down when heavy atoms are involved. This fact motivated the development of new theories of nuclear spin-rotation (SR) tensors, which consider electronic relativistic effects. One was published recently by some of us. In this article we take another step further and propose three different models that generalize Flygare's model. All of them are written using four-component relativistic expressions, though the two-component relativistic SO-S term also appears in one. The first clues for these developments were built from the relationship among σ and the SR tensors within the two-component relativistic LRESC model. Besides, we had to introduce a few other well defined assumptions: (i) relativistic corrections must be included in a way to best reproduce the relationship among the (e-e) term (called "paramagnetic" within the non-relativistic domain) of σ and its equivalent part of the SR tensor, (ii) as happens in Flygare's rule, the shielding of free atoms shall be included to improve accuracy. In the highest accurate model, a new term known as Spin-orbit due to spin, SO-S (in this mechanism the spin-Zeeman Hamiltonian replaces the orbital-Zeeman Hamiltonian), is included. We show the results of the application of those models to halogen containing linear molecules. © 2016 the Owner Societies. Fil:Giribet, C.G. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Aucar, G.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2016 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v18_n34_p23572_Aucar http://hdl.handle.net/20.500.12110/paper_14639076_v18_n34_p23572_Aucar
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
description One of the most influential articles showing the best way to get the absolute values of NMR magnetic shieldings, σ (non-measurables) from both accurate measurements and theoretical calculations, was published a long time ago by Flygare. His model was shown to break down when heavy atoms are involved. This fact motivated the development of new theories of nuclear spin-rotation (SR) tensors, which consider electronic relativistic effects. One was published recently by some of us. In this article we take another step further and propose three different models that generalize Flygare's model. All of them are written using four-component relativistic expressions, though the two-component relativistic SO-S term also appears in one. The first clues for these developments were built from the relationship among σ and the SR tensors within the two-component relativistic LRESC model. Besides, we had to introduce a few other well defined assumptions: (i) relativistic corrections must be included in a way to best reproduce the relationship among the (e-e) term (called "paramagnetic" within the non-relativistic domain) of σ and its equivalent part of the SR tensor, (ii) as happens in Flygare's rule, the shielding of free atoms shall be included to improve accuracy. In the highest accurate model, a new term known as Spin-orbit due to spin, SO-S (in this mechanism the spin-Zeeman Hamiltonian replaces the orbital-Zeeman Hamiltonian), is included. We show the results of the application of those models to halogen containing linear molecules. © 2016 the Owner Societies.
author Giribet, Claudia Gloria
Aucar, Gustavo A.
spellingShingle Giribet, Claudia Gloria
Aucar, Gustavo A.
Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
author_facet Giribet, Claudia Gloria
Aucar, Gustavo A.
author_sort Giribet, Claudia Gloria
title Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
title_short Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
title_full Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
title_fullStr Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
title_full_unstemmed Toward an absolute NMR shielding scale using the spin-rotation tensor within a relativistic framework
title_sort toward an absolute nmr shielding scale using the spin-rotation tensor within a relativistic framework
publishDate 2016
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_14639076_v18_n34_p23572_Aucar
http://hdl.handle.net/20.500.12110/paper_14639076_v18_n34_p23572_Aucar
work_keys_str_mv AT giribetclaudiagloria towardanabsolutenmrshieldingscaleusingthespinrotationtensorwithinarelativisticframework
AT aucargustavoa towardanabsolutenmrshieldingscaleusingthespinrotationtensorwithinarelativisticframework
_version_ 1768546413978845184