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Un oxígeno tetracoordinado perfectamente cuadrado-planar en un polímero de coordinación basado en grupos de
Xian-Ming Zhang1, Jin Lv, Fang Ji
1School of Chemistry and Material Science, Shanxi Normal University, Linfen 041004, China. zhangxm@dns.sxnu.edu.cn
Journal of the American Chemical Society
|March 9, 2011
Resumen
Los investigadores descubrieron un átomo de oxígeno cuadrado-planar, tetracoordinado y único dentro de un polímero a base de cobre. Este hallazgo explica las propiedades magnéticas inusuales y las señales de resonancia de espín de electrones (ESR) observadas en el material.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Química cuántica es la química cuántica.
Sus antecedentes:
- Los polímeros de coordinación ofrecen diversos motivos estructurales.
- Las especies de oxígeno tetracoordinadas son raras e intrigantes.
- Las inusuales propiedades magnéticas y electrónicas impulsan el descubrimiento de materiales.
Objetivo del estudio:
- Para caracterizar una nueva especie de oxígeno tetracoordinado.
- Investigar su entorno estructural y electrónico.
- Para aclarar el origen de las señales magnéticas y ESR observadas.
Principales métodos:
- Síntesis de un polímero de coordinación basado en racimos de tetracopio.
- Difracción de rayos X monocristalino para la determinación estructural.
- Espectroscopia por resonancia de espín de electrones (ESR).
- Cálculos de la Teoría Funcional de la Densidad (DFT).
Principales resultados:
- Observación de un oxígeno tetracoordinado perfectamente cuadrado-planar, D(4h) -simétrico.
- Identificación de un momento magnético inusual asociado con el cúmulo.
- Detección de una señal ESR distinta vinculada a las especies de oxígeno.
- Los cálculos de DFT confirmaron la estabilización del oxígeno cuadrado-planar.
Conclusiones:
- El estudio presenta la primera observación de un oxígeno tetracoordinado cuadrado-planar en esta clase de materiales.
- La coordinación única de oxígeno es responsable de las anomalías magnéticas y ESR observadas.
- Este hallazgo abre nuevas vías para el diseño de materiales con propiedades electrónicas y magnéticas personalizadas.
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