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Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
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Evolución de los complejos supramoleculares luminiscentes de lantánidos M2nL3n desde helicatos y tetraedros hasta
Xiao-Zhen Li1,2, Li-Peng Zhou1, Liang-Liang Yan1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou 350002, People's Republic of China.
Journal of the American Chemical Society
|May 31, 2017
Resumen
Los investigadores lograron el autoensamblaje controlado de las moléculas de lantánidos en diversas estructuras como helicatos, tetraedros y cubos. Estos cubos de lantánidos luminiscentes son prometedores para la detección de explosivos sensibles.
Área de la Ciencia:
- Química de coordinación
- Química supramolecular
- Ciencias de los materiales
Sus antecedentes:
- Las moléculas de lantánidos ofrecen diversas aplicaciones en la ciencia de los materiales y la biología, incluida la detección, la resonancia magnética y la catálisis.
- El autoensamblaje dirigido por coordinación es poderoso para construir sistemas supramoleculares, pero es un desafío para los lantánidos debido a sus propiedades de coordinación variables.
Objetivo del estudio:
- Para demostrar la conmutación estructural sensible durante el autoensamblaje estereocontrolado de compuestos lantánidos.
- Explorar los principios de diseño para la creación de arquitecturas de lantánidos funcionales multinucleares.
Principales métodos:
- Variación sistemática de las distancias de desplazamiento del ligando para controlar los resultados del ensamblaje de los lantánidos.
- Caracterización mediante RMN, ESI-TOF-MS y difracción de rayos X de un solo cristal.
- Investigación del autoensamblaje dependiente de la concentración.
Principales resultados:
- Se ha logrado el autoensamblaje controlado de lantánidos (Ln) y ligandos orgánicos (L) en helicatos Ln2L3, tetraedros Ln4L6 y cubos Ln8L12.
- Se observó un fenómeno de conmutación estructural dictado por el diseño del ligando.
- Se ha demostrado la formación dependiente de la concentración de complejos cúbicos Ln8L12 y su uso como sensores luminiscentes para explosivos como el ácido pícrico.
Conclusiones:
- El diseño de ligandos, específicamente las distancias de compensación, es clave para controlar el autoensamblaje de lantánidos en arquitecturas predecibles.
- Los cubos de lantánido exhiben una alta selectividad y sensibilidad para la detección de apagado de explosivos.
- Proporciona valiosos principios de diseño para futuros sistemas supramoleculares de lantánidos multinucleares.
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