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Síntesis, estructura y comportamiento ferromagnético del complejo de racimo de decacopero (II) apoyado por el
Takashi Kajiwara1, Noriyoshi Kon, Shuichi Yokozawa
1Department of Chemistry, Graduate School of Science, Tohoku University, Aramaki Aoba-ku, Sendai 980-8578, Japan. kajiwara@agnus.chem.tohoku.ac.jp
Journal of the American Chemical Society
|September 19, 2002
Resumen
Hemos sintetizado un nuevo grupo de decacopero de tamaño nanométrico utilizando un ligando tiacalixareno. Este complejo exhibe un comportamiento ferromagnético debido a la disposición única de los iones de cobre.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- Química supramolecular de las moléculas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los tiacalixarenos son versátiles ligandos macrocíclicos capaces de coordinar los iones metálicos.
- El diseño de complejos metálicos polinucleares con propiedades magnéticas específicas es un área clave en la ciencia de los materiales.
Objetivo del estudio:
- Para sintetizar y caracterizar una novela de tamaño nanométrico decacopper (II) complejo de racimo.
- Para investigar las propiedades magnéticas del grupo de cobre sintetizado.
Principales métodos:
- Síntesis del racimo decacopero (II) utilizando el p-tert-butylthiacalix[6]areno como ligando.
- Caracterización estructural utilizando técnicas como la espectrometría de masas de ionización por electrospray (ESI-MS).
- Investigación de las propiedades magnéticas a través de mediciones de susceptibilidad magnética dependientes de la temperatura (chT).
Principales resultados:
- Se sintetizó con éxito un complejo de racimo de decacopero de tamaño nanométrico.
- El ligando calixareno adoptó una conformación de "cono pellizcado", actuando como un ligando no decadente.
- El núcleo del cúmulo, formado por subunidades de pentacopero (II) unidas por grupos hidroxo y oxo, se mantuvo estable en solución.
- Se observó un comportamiento ferromagnético en el núcleo del cúmulo de decacopero (II).
Conclusiones:
- El complejo de cúmulos de decacopero sintetizado es estable y exhibe interesantes propiedades magnéticas.
- El comportamiento ferromagnético observado surge de las interacciones electrónicas específicas entre los iones de cobre (II) dentro del núcleo del cúmulo.
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