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Redes de fosfonatos de metales mezclados Co-Ln y jaulas como refrigerantes magnéticos moleculares
Yan-Zhen Zheng1, Marco Evangelisti, Floriana Tuna
1School of Chemistry, The University of Manchester, Oxford Road, M13 9PL, Manchester, United Kingdom.
Journal of the American Chemical Society
|December 17, 2011
Resumen
Se sintetizaron y estudiaron seis familias de complejos de fosfonato de cobalto-lantanuro y metales mezclados. Los derivados del gadolinio mostraron efectos magnetocalóricos significativos, proporcionales al contenido de gadolinio.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- El magnetismo es el magnetismo.
Sus antecedentes:
- Los fosfonatos de metales mixtos de cobalto-lantanuro son de interés por sus propiedades magnéticas.
- Comprender las relaciones estructura-propiedad es crucial para diseñar nuevos materiales magnéticos.
Objetivo del estudio:
- Para sintetizar y caracterizar seis familias de cobalto-lantanuro mezclado de metales complejos de fosfonato.
- Investigar su diversidad estructural (redes y jaulas) y sus propiedades magnéticas.
- Para evaluar su efecto magnetocalórico (MCE).
Principales métodos:
- Síntesis de complejos de fosfonato de cobalto-lantanuro.
- Caracterización estructural utilizando difracción de rayos X. Caracterización estructural utilizando difracción de rayos X. Caracterización estructural utilizando difracción de rayos X. Caracterización estructural utilizando difracción de rayos X. Caracterización estructural utilizando difracción de rayos X.
- Mediciones de propiedades magnéticas, incluida la determinación del efecto magnetocalórico.
Principales resultados:
- Se sintetizaron seis familias de complejos, que se dividen en tipos estructurales de rejilla y jaula.
- Se observó el efecto magnetocalórico máximo para los derivados del gadolinio.
- Los cambios de entropía para los derivados de gadolinio oscilaron entre 11,8 y 28,6 J kg{-1) K{-1) a 3 K y 7 T.
- Se encontró que el MCE era proporcional al contenido de gadolinio en los complejos.
Conclusiones:
- El estudio reporta nuevos complejos de fosfonato de cobalto-lantanuro con estructuras diversas.
- Los complejos basados en gadolinio muestran propiedades magnetocalóricas prometedoras.
- El MCE observado está directamente relacionado con la proporción de gadolinio, ofreciendo un principio de diseño para materiales de refrigeración magnética.
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