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Transformación inducida por solvente de cristales simples de un compuesto de espín cruzado (SCO) a cristales simples

Bao Li¹, Rong-Jia Wei, Jun Tao

¹State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China.

Journal of the American Chemical Society

|January 21, 2010

Resumen

Los investigadores obtuvieron la estructura cristalina de un complejo de cruce de espín (SCO), Fe ((tpa) ((NCS) ((2). La exposición al vapor de metanol lo transformó en un nuevo compuesto de SCO con una transición de espín de dos pasos, lo que demuestra un método sutil para afinar las propiedades de SCO.

Área de la Ciencia:

Química Inorgánica La Química Inorgánica es la química inorgánica.
Ciencia de los materiales Ciencia de los materiales.
Química del estado sólido.

Sus antecedentes:

Los complejos Spin-Crossover (SCO) exhiben cambios de estado de giro dependientes de la temperatura.
Comprender la estructura cristalina de los complejos SCO es crucial para correlacionar la estructura con las propiedades.
Fe ((tpa) ((NCS) ((2) es un complejo SCO bien estudiado cuya estructura cristalina se determinó recientemente.

Objetivo del estudio:

Obtener la estructura cristalina de Fe ((tpa) ((NCS) ((2)) y correlacionar su transición de espín con las estructuras de estado sólido.
Para investigar la transformación de un solo cristal a un solo cristal de Fe (tpa) (NCS) (2) tras la exposición al vapor de metanol.
Para caracterizar el comportamiento SCO y la estructura cristalina del nuevo compuesto metanol-adducto.

Principales métodos:

Difracción de rayos X monocristalino a varias temperaturas. difracción de rayos X monocristalino a varias temperaturas.
Exposición de cristales únicos al vapor de metanol.
Mediciones de la susceptibilidad magnética.
Espectroscopia de Mössbauer. también conocida como espectroscopia de Mössbauer.

Principales resultados:

Se obtuvo la estructura cristalina de Fe ((tpa) ((NCS) ((2), revelando una transición de espín incompleta de un solo paso.
Se produjo una transformación de un solo cristal a un solo cristal al exponerse al vapor de metanol, formando un nuevo compuesto SCO con un cambio de color dramático.
El nuevo compuesto exhibió una transición de espín completa en dos pasos (LS-LS a HS-HS a través de LS-HS), con dos centros SCO independientes resueltos cristalográficamente.
La transformación mantuvo una parte significativa de la estructura cristalina original, lo que indica un método de modificación sutil.

Conclusiones:

La sorción de disolventes proporciona un método eficiente y sutil para modificar las propiedades de SCO.
Este enfoque permite ajustar y optimizar los compuestos SCO.
La perturbación heterogénea de las matrices supramoleculares de SCO es propicia para descubrir nuevos sistemas y fenómenos de SCO para aplicaciones de materiales.

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