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Redox apagado del acoplamiento ferromagnético en un tricobalto de espín mixto (II) mesocato triple

Marie-Claire Dul¹, Emilio Pardo, Rodrigue Lescouëzec

¹Institut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie-Paris 6, UMR 7201, F-75252 Paris, France.

Journal of the American Chemical Society

|September 26, 2009

Resumen

Los investigadores desarrollaron un nuevo marco metálico-orgánico basado en cobalto que actúa como un interruptor. Este material exhibe propiedades magnéticas distintas en sus dos estados redox, ofreciendo potencial para nuevas aplicaciones electrónicas.

Área de la Ciencia:

Química Inorgánica La Química Inorgánica es la química inorgánica.
Ciencia de los materiales Ciencia de los materiales.
Magnetoquímica es la Magnetoquímica.

Sus antecedentes:

Las estructuras metal-orgánicas (MOF) son prometedoras para aplicaciones avanzadas.
El desarrollo de materiales magnéticos conmutables es un desafío clave en la ciencia de los materiales.
Los complejos de cobalto ofrecen propiedades electrónicas y magnéticas sintonizables.

Objetivo del estudio:

Para sintetizar y caracterizar un nuevo mesocato de oxalamida de cobalto trinuclear.
Para investigar las propiedades magnéticas redox-dependientes del complejo de cobalto.
Establecer una base para los "interruptores metal-orgánicos" basados en redox.

Principales métodos:

Síntesis de un mesocato triple de oxalamida de cobalto trinuclear.
Estudios electroquímicos para determinar los estados redox.
Mediciones de susceptibilidad magnética para sondear el acoplamiento magnético.

Principales resultados:

El compuesto existe en dos estados redox: un estado homovalente de tricobalto (II) y un estado heterovalente de tricobalto (II,III,II).
El estado reducido de tricobalto exhibe acoplamiento ferromagnético entre los iones terminales de cobalto.
La oxidación al estado de tricobalt ((II,III,II) desacopla los iones terminales de cobalto, alterando las propiedades magnéticas.

Conclusiones:

Un nuevo mesocato de cobalto demuestra un comportamiento magnético conmutable basado en el estado redox.
Este sistema sirve como un preludio a los "interruptores metales-orgánicos" ferromagnéticos basados en redox.
Los hallazgos abren vías para el diseño de materiales magnéticos sensibles.

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