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Espectro infrarrojo del anión cis- y trans-peroxinitrito, OONO-, en el argón sólido

B Liang¹, L Andrews

¹Department of Chemistry, University of Virginia, P.O. Box 400319, Charlottesville, VA 22904-4319, USA.

Journal of the American Chemical Society

|October 5, 2001

Resumen

Los investigadores identificaron nuevos isómeros de aniones cis- y trans-peroxinitrito utilizando técnicas de ablación láser y aislamiento de matriz. Estos isómeros son cruciales para comprender el peroxinitrito.

Área de la Ciencia:

Química Inorgánica La Química Inorgánica es la química inorgánica.
La bioquímica es la bioquímica.
La espectroscopia es una técnica de espectroscopia.

Sus antecedentes:

El anión peroxinitrito (OONO-) es vital en la bioquímica, formado por el óxido nítrico (NO) y el superóxido (O2-).
Estudios anteriores carecían de una caracterización detallada de los isómeros del anión peroxinitrito.

Objetivo del estudio:

Para identificar y caracterizar nuevos isómeros del anión peroxinitrito.
Para investigar las vías de formación y la fotoisomerización de los aniones de peroxinitrito.

Principales métodos:

La ablación láser de objetivos metálicos con codificación concurrente de NO y O2 en matrices de argón a 7 K.
Espectroscopia infrarroja y etiquetado isotópico (15NO, 18O2) para elucidación estructural.
Cálculos de la Teoría Funcional de Densidad (DFT) para el análisis de frecuencia.

Principales resultados:

Se observaron nuevas bandas infrarrojas independientes de los metales, asignadas a los isómeros de aniones cis- y trans-peroxinitrito.
Los desplazamientos isotópicos y los cálculos de DFT confirmaron las asignaciones.
Los aniones se formaron a través de reacciones iónico-moleculares y son fotoisomerizables.

Conclusiones:

El estudio identificó y caracterizó con éxito los isómeros de aniones cis- y trans-peroxinitrito.
La formación involucra O2- y NO, siendo crítico el estabilizador de la matriz.
La fotoisomerización proporciona una nueva dimensión para la comprensión de la química de la peroxinitrita.

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