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Bistabilidad múltiple y tristabilidad con conversiones de estado de espín dual en [Fe(dpp) ][Ni(mnt) ]2 x MeNO22
Masayuki Nihei1, Hirotaka Tahira, Nobukazu Takahashi
1Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan.
Journal of the American Chemical Society
|February 18, 2010
Resumen
Este estudio revela un nuevo compuesto de coordinación de hierro-níquel que exhibe múltiples conversiones de estado de espín. Estas transiciones de espín, influenciadas por la temperatura, involucran tanto componentes de hierro como de níquel, lo que lleva a distintas fases de alta temperatura y baja temperatura.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- Ciencia de los materiales Ciencia de los materiales.
- Física del estado sólido Física del estado sólido
Sus antecedentes:
- Los sistemas multicomponentes ofrecen propiedades únicas a través de la interacción de diferentes iones.
- Las transiciones de estado de giro en complejos de metales de transición son cruciales para el desarrollo de materiales avanzados.
- La comprensión de estas transiciones requiere una caracterización estructural y magnética detallada.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo sistema multicomponente que contiene hierro y níquel.
- Para investigar las conversiones de estado de espín dependientes de la temperatura en los componentes catiónicos y aniónicos.
- Para dilucidar las propiedades estructurales y magnéticas asociadas con diferentes fases.
Principales métodos:
- Análisis estructural de rayos X de temperatura variable.
- Mediciones de la susceptibilidad magnética.
- Mediciones de la capacidad térmica.
- (57) Espectroscopia de Fe Mossbauer.
Principales resultados:
- El compuesto sintetizado [Fe (dpp) ] [Ni (mnt) ] exhibe múltiples conversiones de estado de espín.
- La fase de alta temperatura presenta hierro de alto espín y níquel monomérico con S=1/2.2.
- La fase de baja temperatura muestra hierro de baja espina y níquel diamagnético y dimerizado.
- Las fases intermedias muestran estados de espín mixtos y una variada dimerización del níquel.
- Transición de giro inducida por la luz observada en el sitio del hierro a 5 K.
Conclusiones:
- El sistema multicomponente demuestra complejas dinámicas de estado de giro impulsadas por la temperatura.
- Los cambios estructurales, incluida la dimerización del níquel, se correlacionan con las transiciones de estado de giro.
- El compuesto exhibe potencial para el comportamiento magnético sensible a la luz.
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