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Una nueva red uniforme de autopenetración, (8,4) (o 8(6)), que contiene nodos planos de cuatro coordenadas
Ming-Liang Tong1, Xiao-Ming Chen, Stuart R Batten
1School of Chemistry & Chemical Engineering and State Key Laboratory of Optoelectronic Materials & Technologies, Sun Yat-Sen University, Guangzhou 510275, PR China. cestml@zsu.edu.cn
Journal of the American Chemical Society
|December 25, 2003
Resumen
Los investigadores sintetizaron nuevos polímeros de coordinación basados en níquel utilizando reacciones hidrotermales. Se observaron diferentes polimorfas a diferentes temperaturas, revelando topologías de red 3D únicas y cadenas 1D.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
- Coordinación Química de la Coordinación
Sus antecedentes:
- Los polímeros de coordinación son materiales con diversas aplicaciones, impulsados por sus estructuras sintonizables.
- La síntesis hidrotermal es un método clave para crear materiales cristalinos.
- Comprender las topologías de red es crucial para diseñar materiales con propiedades específicas.
Objetivo del estudio:
- Para investigar la formación de polímeros de coordinación a base de níquel a través de la síntesis hidrotermal.
- Para caracterizar diferentes polimorfas obtenidas a diferentes temperaturas.
- Para dilucidar las topologías de red únicas de los materiales sintetizados.
Principales métodos:
- Reacciones hidrotermales que involucran el ácido 3-(3-piridil) acrílico (pyaraH), NiCl2 y NaOH.
- La cristalización a diferentes temperaturas (180°C y 150°C).
- Análisis estructural de las polimorfas resultantes.
Principales resultados:
- Formación de dos polimorfos: alfa-Ni ((pyara) 2 ((H2O) 2 a 180 °C y una fase beta a 150 °C.
- La fase alfa exhibe una nueva topología de red de cuatro coordenadas (8,4) auto-penetrante (símbolo de Schläfli 86), distinta de las redes uniformes previamente conocidas.
- La fase beta consiste en cadenas 1D interconectadas en una red 3D a través de enlaces de hidrógeno.
Conclusiones:
- La síntesis hidrotermal ofrece una ruta a diversas estructuras poliméricas de coordinación de níquel.
- Se ha identificado una topología de red fundamental no reconocida anteriormente.
- La temperatura juega un papel crítico en dictar la estructura final y la dimensionalidad de los polímeros de coordinación.
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