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Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
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Propiedades de deslizamiento de anillo y redox de múltiples electrones de los complejos Fe/Ru/Os-bis (areno): ¿el
Richard L Lord1, Cynthia K Schauer, Franklin A Schultz
1Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|September 8, 2011
Resumen
Los complejos bis ((hexametilbenceno) de los metales del grupo 8 exhiben diversos mecanismos de transferencia de electrones. Los cambios de hapticidad, impulsados por la unión, controlan el comportamiento aparente de los multielectrones en estos compuestos de metales de transición.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- La electroquímica es electroquímica.
Sus antecedentes:
- Los complejos metálicos (Fe, Ru, Os) del grupo 8 bis (hexametilbenceno) muestran un comportamiento redox variado.
- Los mecanismos de transferencia de electrones y la termodinámica difieren significativamente entre las series M(II) → M(I) → M(0).
- Conjeturas anteriores vincularon la hapticidad de Fe(0) con las transferencias secuenciales de electrones.
Objetivo del estudio:
- Investigar los mecanismos de transferencia de electrones de los complejos del grupo 8 bis (hexametilbenceno).
- Para dilucidar el papel de los cambios de hapticidad en el control del comportamiento redox.
- Desarrollar un modelo conceptual para la comprensión de la química redox de d(6) bis((areno).
Principales métodos:
- Se emplearon cálculos de la Teoría Funcional de Densidad (DFT).
- Se utilizó un modelo de química establecido.
- Se realizaron experimentos electroquímicos.
Principales resultados:
- El complejo Fe muestra distintos potenciales redox; Ru exhibe potenciales superpuestos; Os muestra una transferencia de dos electrones.
- El cambio de hapticidad es una consecuencia de la unión, que influye en la unión de electrones.
- El estado favorecido de Fe ((0) es el triplet η ((6):η ((6), no el estado propuesto η ((4):η ((6).
- Ru y Os utilizan diferentes mecanismos basados en cuándo ocurre el cambio de hapticidad.
Conclusiones:
- El cambio de hapticidad por sí solo no garantiza el comportamiento multielectrónico.
- El apego vertical de los electrones dicta aparentes eventos redox multielectrónicos.
- Se estableció un modelo general para el comportamiento redox de d(6) bis(areno, aplicable más allá de la tríada Fe.
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