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A {Gd12Na6} Rueda Cuadruple Molecular con un Efecto Magnetocalórico de registro en bajos campos magnéticos y
Thomais G Tziotzi1, David Gracia2, Scott J Dalgarno3
1Department of Chemistry, University of Crete, Voutes 71003, Herakleion, Greece.
Journal of the American Chemical Society
|April 3, 2023
Resumen
Los investigadores sintetizaron un nuevo compuesto basado en gadolinio que exhibe un efecto magnetocalórico récord. Este material muestra potencial para una refrigeración magnética eficiente a bajas temperaturas y campos magnéticos.
Área de la Ciencia:
- Química inorgánica
- Ciencias de los materiales
- El magnetismo
Sus antecedentes:
- Los compuestos a base de lantánidos se exploran por sus propiedades magnéticas únicas.
- El efecto magnetocalórico (MCE) es crucial para el desarrollo de tecnologías de refrigeración avanzadas.
- El diseño de imanes moleculares con MCE significativo a bajas temperaturas sigue siendo un desafío.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo complejo polinuclear gadolinio-sodio.
- Investigar las propiedades magnéticas y el efecto magnetocalórico del compuesto sintetizado.
- Establecer un nuevo récord para el efecto magnetocalórico en materiales moleculares en campos bajos.
Principales métodos:
- Reacción asistida con disolvente del acetato de gadolinio, el saliciladehído y el metóxido de sodio.
- Difracción de rayos X de un solo cristal para la determinación estructural del complejo de ruedas cuádruples.
- Mediciones de la susceptibilidad magnética para analizar las interacciones magnéticas y el efecto magnetocalórico.
Principales resultados:
- Se sintetizó con éxito un nuevo complejo de ruedas cuádruples, [Gd12Na6(OAc) 25 ((HCO2) 5 ((CO3) 6 ((H2O) 12 · 9H2O · 0.5MeCN.
- La estructura cristalina revela una disposición única de iones GdIII y Na+ en anillos {Gd6} y {Na3}.
- Se observaron interacciones antiferromagnéticas débiles entre los iones GdIII, lo que condujo a un MCE récord de - ΔSm = 29,3 J kg-1 K-1 a 1 T y 0,5 K.
Conclusiones:
- El complejo Gd-Na sintetizado demuestra excepcionales propiedades magnetocalóricas.
- Este compuesto establece un nuevo punto de referencia para los materiales moleculares en el enfriamiento magnético de campo bajo.
- Los hallazgos ponen de relieve el potencial de diseñar estructuras polinucleares complejas para una refrigeración magnética eficiente.
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