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Abstract:

The broadly accepted procedure to obtain the experimental absolute scale of NMR magnetic shieldings, σ, is well-known for nonheavy atom-containing molecules. It was uncovered more than 40 years ago by the works of Ramsey and Flygare. They found a quite accurate relationship among σ and the nuclear spin-rotation constants. Its relativistic extension was very recently proposed, although it has an intrinsic weakness because a new SO-S two-component term needs to be considered. We show how to overcome this problem. We found that (νY S - νY atom,S) generalizes the SO-S term, where νY S = ⟨⟨[((r - rY) × α)/(|r - rY|3)]; S(4)⟩⟩, r - rY is the electron position with respect to the position of nucleus Y, and S(4) is the four-component total electron spin. When including this new term, one finds that the best of our relativistic Flygare-like models fits quite well with the results of the most accurate method available at the moment. We also show that the difference among the parallel component of σ(Xe) in XeF2 and σ(Xe) of the free atom is almost completely described by that new term. © 2016 American Chemical Society.

Registro:

Documento: Artículo
Título:Role of Spin-Dependent Terms in the Relationship among Nuclear Spin-Rotation and NMR Magnetic Shielding Tensors
Autor:Aucar, I.A.; Gomez, S.S.; Giribet, C.G.; Aucar, G.A.
Filiación:Instituto de Modelado e Innovación Tecnológica, CONICET, Departamento de Física, FCENA-UNNE, Avda. Libertad 5460, Corrientes, W3404AAS, Argentina
Instituto de Fı́sica de Buenos Aires, CONICET, Departamento de Fı́sica, FCEN-UBA, Ciudad Universitaria, Buenos Aires, C1428EGA, Argentina
Palabras clave:Atoms; Electrospinning; Magnetic moments; Magnetic shielding; Shielding; Spin dynamics; Electron spins; Free atoms; New terms; Nuclear spins; Parallel component; Two-component; Nuclear magnetic resonance
Año:2016
Volumen:7
Número:24
Página de inicio:5188
Página de fin:5192
DOI: http://dx.doi.org/10.1021/acs.jpclett.6b02361
Título revista:Journal of Physical Chemistry Letters
Título revista abreviado:J. Phys. Chem. Lett.
ISSN:19487185
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19487185_v7_n24_p5188_Aucar

Referencias:

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Citas:

---------- APA ----------
Aucar, I.A., Gomez, S.S., Giribet, C.G. & Aucar, G.A. (2016) . Role of Spin-Dependent Terms in the Relationship among Nuclear Spin-Rotation and NMR Magnetic Shielding Tensors. Journal of Physical Chemistry Letters, 7(24), 5188-5192.
http://dx.doi.org/10.1021/acs.jpclett.6b02361
---------- CHICAGO ----------
Aucar, I.A., Gomez, S.S., Giribet, C.G., Aucar, G.A. "Role of Spin-Dependent Terms in the Relationship among Nuclear Spin-Rotation and NMR Magnetic Shielding Tensors" . Journal of Physical Chemistry Letters 7, no. 24 (2016) : 5188-5192.
http://dx.doi.org/10.1021/acs.jpclett.6b02361
---------- MLA ----------
Aucar, I.A., Gomez, S.S., Giribet, C.G., Aucar, G.A. "Role of Spin-Dependent Terms in the Relationship among Nuclear Spin-Rotation and NMR Magnetic Shielding Tensors" . Journal of Physical Chemistry Letters, vol. 7, no. 24, 2016, pp. 5188-5192.
http://dx.doi.org/10.1021/acs.jpclett.6b02361
---------- VANCOUVER ----------
Aucar, I.A., Gomez, S.S., Giribet, C.G., Aucar, G.A. Role of Spin-Dependent Terms in the Relationship among Nuclear Spin-Rotation and NMR Magnetic Shielding Tensors. J. Phys. Chem. Lett. 2016;7(24):5188-5192.
http://dx.doi.org/10.1021/acs.jpclett.6b02361