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Imán híbrido sensible a estímulos: ajuste del cruce de espín fotoinducido en complejos de Fe (III) insertados en
Miguel Clemente-León1, Eugenio Coronado, Maurici López-Jordà
1Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain. miguel.clemente@uv.es
Journal of the American Chemical Society
|May 17, 2013
Resumen
Los nuevos imanes híbridos exhiben tanto el ordenamiento magnético como el cruce de espín fotoinducido (efecto LIESST). Estos materiales integran cationes complejos de hierro en redes de oxalato, mostrando potencial para aplicaciones magnéticas avanzadas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química del estado sólido.
- El magnetismo es el magnetismo.
Sus antecedentes:
- Los imanes híbridos combinan diferentes componentes magnéticos.
- Los materiales de espín-crossover cambian sus estados de espín bajo estímulos externos.
- El efecto LIESST es un fenómeno clave en la ciencia de los materiales.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos imanes híbridos.
- Para investigar la coexistencia del ordenamiento magnético y el cruce de espín fotoinducido.
- Para explorar la influencia de las moléculas de disolventes en las propiedades de los materiales.
Principales métodos:
- Cristalización de compuestos híbridos.
- Mediciones de las propiedades magnéticas.
- Espectroscopia de Mössbauer. también conocido como espectroscopia de Mössbauer.
- Caracterización espectroscópica. caracterización espectroscópica.
Principales resultados:
- Sintetizó tres imanes híbridos con cationes [Fe{\sal2-trien) ]{\+} en una red 2D de oxalato.
- Se observó la coexistencia del ordenamiento ferromagnético (5.6 K) y el cruce de espín (efecto LIESST).
- Se ha demostrado que la cooperatividad no es esencial para el efecto LIESST en los compuestos Fe (III).
Conclusiones:
- Los imanes híbridos sintetizados exhiben funciones magnéticas duales.
- Las moléculas de disolventes juegan un papel en la intercalación y las propiedades de estos materiales.
- El efecto LIESST puede ocurrir en compuestos Fe ((III) incluso sin cooperatividad.
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