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Dependencia notable de la velocidad de escaneo para un complejo de cruce de espín de hierro dinuclear altamente

Rafal Kulmaczewski¹, Juan Olguín, Jonathan A Kitchen

¹Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago , P.O. Box 56, Dunedin 9054, New Zealand.

Journal of the American Chemical Society

|January 10, 2014

Resumen

Un nuevo complejo de diironio exhibe un cruce de espín abrupto, logrando un ancho de bucle de histeresis récord para complejos dinucleares. Su dependencia de la velocidad de enfriamiento ofrece información sobre la dinámica de la transición de giro.

Área de la Ciencia:

Coordinación Química de la Coordinación
Ciencia de los materiales Ciencia de los materiales.
El magnetismo es el magnetismo.

Sus antecedentes:

Los complejos de cruce de espín (SCO) son interruptores moleculares que responden a estímulos externos.
Los complejos SCO dinucleares ofrecen efectos cooperativos únicos y potencial para un comportamiento magnético complejo.

Objetivo del estudio:

Sintetizar y caracterizar un nuevo complejo de diironio (II) basado en triazol.
Para investigar las propiedades del cruce de espín, incluida la histeresis térmica y la dependencia de la velocidad de escaneo.

Principales métodos:

Síntesis de un nuevo complejo de diironio (II) a base de triazol.
Mediciones de la susceptibilidad magnética utilizando un magnetómetro SQUID.
Calorimetría de barrido diferencial (DSC) para el análisis térmico.
Espectroscopia de Mössbauer para la investigación detallada de la estructura electrónica.

Principales resultados:

El complejo muestra transiciones bruscas de cruce de espín entre los estados de alto espín (HS) y bajo espín (LS).
Se observó un ancho de bucle de histeresis térmica equivalente al récord (ΔT = 22 K) para un complejo dinuclear.
Se encontró una notable dependencia de la velocidad de escaneo exclusivamente en la rama de enfriamiento del bucle de histeresis.

Conclusiones:

El nuevo complejo de diiron (II) demuestra un cruce de espín eficiente con una cooperación significativa.
La histeresis observada y la dependencia de la velocidad de escaneo resaltan el potencial del complejo para aplicaciones de conmutación molecular.
Este estudio contribuye a la comprensión de la dinámica de espín en los sistemas dinucleares SCO.

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