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Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
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Un imán de una sola molécula basado en heptacianomolibdato con la barrera de energía más alta para un compuesto de
Kun Qian1, Xing-Cai Huang, Chun Zhou
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
Journal of the American Chemical Society
|August 24, 2013
Resumen
Los investigadores desarrollaron nuevas moléculas de manganeso-molibdeno (Mn2Mo), incluido el primer imán de una sola molécula (SMM) utilizando heptacianomolibdato. Estas moléculas exhiben propiedades récord para los SMM basados en cianuro.
Área de la Ciencia:
- El magnetismo molecular es el magnetismo molecular.
- Coordinación Química de la Coordinación
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los imanes de una sola molécula (SMM) son materiales moleculares que exhiben una lenta relajación magnética.
- Los SMM basados en cianuro ofrecen propiedades magnéticas sintonizables a través del diseño de ligandos.
- Los aniones orbitales degenerados presentan oportunidades para el desarrollo de nuevos SMM.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevas moléculas trinucleares Mn2Mo.
- Para investigar las propiedades magnéticas de estos nuevos sistemas moleculares.
- Para explorar el potencial de los aniones de heptacianomolibdato en SMM.
Principales métodos:
- Síntesis de tres complejos trinucleares de Mn2Mo.
- Difracción de rayos X monocristalino para la determinación estructural.
- Susceptibilidad magnética y mediciones de magnetización de corriente continua (dc).
Principales resultados:
- Preparación exitosa de tres moléculas de Mn2Mo que incluyen el anión [Mo(CN) 7) ((4-).
- Descubrimiento del primer SMM basado en heptacianomolybdate.
- Registre la temperatura de bloqueo y la barrera de energía (U = 40,5 cm(-1)) para SMM basados en cianuro.
- Observación de amplios bucles de histeresis y pasos de túnel cuántico en cristales únicos.
Conclusiones:
- El anión [Mo(CN) [7](4-) es un bloque de construcción viable para SMM de alto rendimiento.
- Estos hallazgos avanzan en el campo del magnetismo molecular, particularmente para los sistemas basados en cianuro.
- Las propiedades observadas allanan el camino para futuros diseños de materiales magnéticos avanzados.
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