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Cruce de giro de múltiples pasos programable por invitado en un material poroso de tipo Hofmann 2D
Michael J Murphy1, Katrina A Zenere1, Florence Ragon1
1School of Chemistry, The University of Sydney , Sydney, NSW 2006, Australia.
Journal of the American Chemical Society
|January 4, 2017
Resumen
Este estudio introduce un nuevo material de cruce de espín (SCO) con interacciones elásticas frustradas. El intercambio de invitados dentro de este marco permite transiciones de giro ajustables en varios pasos, avanzando en la investigación de materiales intercambiables.
Área de la Ciencia:
- Ciencias de los materiales
- Química del estado sólido
- Química de coordinación
Sus antecedentes:
- Los materiales de cruce de espín (SCO) exhiben propiedades intercambiables impulsadas por transiciones cooperativas.
- Las transiciones SCO de varios pasos son deseables para el almacenamiento de datos, pero requieren interacciones elásticas controladas.
- Las interacciones antagónicas, como las fuerzas ferroelásticas y antiferroelásticas competidoras, pueden generar distorsiones complejas de la red.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo marco de SCO, [FeII (bztrz) 2 (PdII (CN) 4) ] · n (invitado), capaz de apoyar las interacciones antagónicas.
- Investigar la influencia del intercambio de invitados en el comportamiento de la OCS en este marco.
- Explorar la relación entre la frustración elástica y la naturaleza de las transiciones de giro.
Principales métodos:
- Síntesis del marco SCO de tipo 2-D de Hofmann [FeII (bztrz) 2 (pdII (CN) 4) ]·n (invitado).
- Caracterización de la estructura del material y su sistema de poros invitados duales.
- Investigar el comportamiento de la SCO a través de experimentos de intercambio de invitados y análisis de las características de la transición de giro.
Principales resultados:
- El material sintetizado exhibe un comportamiento SCO intrínsecamente frustrado debido a las interacciones ferro- y antiferroelásticas en competencia.
- El intercambio de invitados moduló con éxito el comportamiento de la OCS, produciendo transiciones de uno, dos y tres pasos, así como la desactivación de la OCS.
- El grado de frustración elástica y la complejidad resultante de la transición de espín son sintonizables a través de la manipulación de invitados moleculares.
Conclusiones:
- El nuevo marco de la OCS demuestra una plataforma versátil para lograr diversos comportamientos de transición.
- La frustración elástica, manipulada por las moléculas huéspedes, es un factor clave en el control de la conmutación SCO en múltiples pasos.
- Este trabajo sugiere que las características estructurales sutiles contribuyen a la conmutación en múltiples pasos en los materiales SCO, abriendo nuevas vías para el diseño de materiales.
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