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Síntesis e identificación espectroscópica de un complejo mu-1,2-disulfidodinickel
Matthew T Kieber-Emmons1, Katherine M Van Heuvelen, Thomas C Brunold
1Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Journal of the American Chemical Society
|December 23, 2008
Resumen
Los investigadores sintetizaron un nuevo complejo dinickel (II) con un enlace disulfido mediante la reducción del azufre elemental. La espectroscopia y los cálculos avanzados confirmaron sus propiedades electrónicas y estructurales únicas, incluida una banda de transferencia de carga distintiva.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Coordinación Química de la Coordinación
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- La reducción elemental del azufre es crucial para la síntesis de compuestos inorgánicos que contienen azufre.
- Los complejos de níquel juegan un papel importante en la catálisis y la ciencia de los materiales.
- La caracterización de los enlaces metal-azufre requiere técnicas analíticas avanzadas.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo dinickel (II) con un enlace disulfido.
- Para dilucidar la estructura electrónica y la unión del núcleo Ni(2) S(2).
- Para investigar las propiedades vibratorias asociadas con el enlace S-S.
Principales métodos:
- Reducción del azufre elemental utilizando un precursor monovalente del níquel.
- Métodos espectroscópicos avanzados que incluyen UV-Vis y espectroscopia Raman de resonancia.
- Cálculos de la Teoría Funcional de Densidad (DFT) para el análisis estructural y electrónico.
Principales resultados:
- Síntesis exitosa de un complejo trans-1,2-mu-disulfidodinickel (II) complejo.
- Identificación de una intensa transición de transferencia de carga S --> Ni a 650 nm.
- Observación de un modo de estiramiento S-S sensible al isótopo a 474 cm (-1) indicando la distorsión del núcleo.
Conclusiones:
- El estudio caracterizó con éxito un nuevo complejo disulfido de dinickel.
- Los datos espectroscópicos y computacionales proporcionan información sobre la unión metal-azufre y las transiciones electrónicas.
- Los hallazgos contribuyen a la comprensión de la química de coordinación del azufre en los complejos de metales de transición.
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