Borazine: To be or not to be aromatic

Rafael Islas, Eduardo Chamorro, Juvencio Robles, Thomas Heine, Juan C. Santos, Gabriel Merino

Resultado de la investigación: Article

108 Citas (Scopus)

Resumen

Aromaticity of borazine, which has been subject of controversial discussions, is addressed. Beside a short review on aromaticity of borazine we report a detailed analysis of two molecular fields, the induced magnetic field (Bind) and the electron localization function (ELF). The induced magnetic field of borazine shows a long-range shielding cone perpendicular to the molecular plane, as in benzene, but lower in magnitude. Contrary to benzene, borazine shows two weakly paratropic regions, one of them inside the ring, and the second one enveloping the boron atoms. It is necessary to separate σ and π contributions to identify whether borazine exhibits π-aromatic character comparable to benzene. Nucleus-independent chemical shift (NICS) isolines show that the σ electrons are much stronger localized than π electrons, their local paramagnetic contributions generate a short-range response and a paratropic (deshielding) region in the ring center (similar to an anti-aromatic response). Three regions can be identified as chemically meaningful domains exhibiting an internally strong electron delocalization (ELF = 0.823). Borazine may be described as a π aromatic compound, but it is not a globally aromatic species, as the electronic system is not as delocalized as in benzene.

Idioma originalEnglish
Páginas (desde-hasta)833-839
Número de páginas7
PublicaciónStructural Chemistry
Volumen18
N.º6
DOI
EstadoPublished - 1 dic 2007

Huella dactilar

Benzene
benzene
Electrons
electrons
aromatic compounds
Magnetic fields
rings
Boron
magnetic fields
Aromatic compounds
Chemical shift
shielding
chemical equilibrium
cones
boron
Shielding
borazine
Cones
nuclei
Atoms

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Citar esto

Islas, Rafael ; Chamorro, Eduardo ; Robles, Juvencio ; Heine, Thomas ; Santos, Juan C. ; Merino, Gabriel. / Borazine : To be or not to be aromatic. En: Structural Chemistry. 2007 ; Vol. 18, N.º 6. pp. 833-839.
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Borazine : To be or not to be aromatic. / Islas, Rafael; Chamorro, Eduardo; Robles, Juvencio; Heine, Thomas; Santos, Juan C.; Merino, Gabriel.

En: Structural Chemistry, Vol. 18, N.º 6, 01.12.2007, p. 833-839.

Resultado de la investigación: Article

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AU - Chamorro, Eduardo

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AU - Heine, Thomas

AU - Santos, Juan C.

AU - Merino, Gabriel

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