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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
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Las drásticas transformaciones de un solo cristal a un solo cristal inducidas por la temperatura o el invitado de un
Jie-Peng Zhang1, Yan-Yong Lin, Wei-Xiong Zhang
1State Key Laboratory of Photoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
Journal of the American Chemical Society
|October 13, 2005
Resumen
Los investigadores descubrieron un nuevo polímero de coordinación nanoporoso que cambia su estructura cuando los huéspedes son absorbidos o desorbados. Este material sufre una transformación de 5 a 6 veces la interpenetración neta, ofreciendo potencial para aplicaciones de materiales inteligentes.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- Los polímeros de coordinación son materiales cristalinos con diversas aplicaciones.
- Los materiales nanoporosos ofrecen propiedades sintonizables basadas en las interacciones de las moléculas invitadas.
- Las transformaciones estructurales en los polímeros de coordinación son clave para desarrollar materiales sensibles.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo polímero de coordinación nanoporoso.
- Para investigar los cambios estructurales inducidos por la desorción/absorción del huésped.
- Explorar el potencial de las transformaciones monocristalinas a monocristalinas en polímeros de coordinación.
Principales métodos:
- Se utilizó la difracción de rayos X monocristalino para determinar la estructura cristalina.
- El análisis termogravimétrico (TGA) se empleó para estudiar la desorción del huésped.
- La difracción de rayos X en polvo de temperatura variable (PXRD) se utilizó para monitorear los cambios estructurales.
Principales resultados:
- Se sintetizó un nuevo polímero de coordinación, [Ag6Cl(atz) 4].OH.6H2O.
- El material exhibe redes de coordinación interpenetradas de Ag3 ((atz) 2).
- Se observó una transformación de un solo cristal a un solo cristal de interpenetración neta de 5 a 6 veces después de la desorción / absorción del huésped, además de una transformación inducida por la temperatura.
Conclusiones:
- El polímero de coordinación sintetizado demuestra un comportamiento sensible a las moléculas invitadas.
- La transformación estructural observada pone de relieve la naturaleza dinámica de las redes de coordinación interpenetradas.
- Este material es prometedor para aplicaciones en tecnologías de detección de huéspedes y separación.
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