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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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Luminiscencia circularmente polarizada visible del helicato circular octanuclear
Yan Bing Tan1, Yoshinori Okayasu2, Shohei Katao1
1Graduate School of Science and Technology, Division of Materials Science, Nara Institute of Science and Technology, NAIST, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Journal of the American Chemical Society
|September 22, 2020
Resumen
Este estudio introduce nuevos helicatos de lantánidos circulares quirales con estructuras antiprisma cuadradas únicas. Estos complejos exhiben una fuerte luminiscencia circularmente polarizada, allanando el camino para materiales ópticos avanzados.
Área de la Ciencia:
- Química de coordinación
- Química supramolecular
- La fotofísica
Sus antecedentes:
- Los complejos de lantánidos (LnIII) son cruciales para las aplicaciones de luminiscencia.
- Los helicatos quirales ofrecen propiedades estructurales y fotofísicas únicas.
- La luminiscencia polarizada circular (CPL) es vital para las tecnologías ópticas avanzadas.
Objetivo del estudio:
- Sintetizar y caracterizar los nuevos helicatos de lantánidos circulares octanucleares simétricos D4.
- Investigar las características estructurales y las propiedades fotofísicas, incluida la actividad de CPL.
- Para explorar el potencial de estos helicatos en materiales ópticos quirales.
Principales métodos:
- Síntesis de helicatos circulares octanucleares utilizando la piridina quiral bis ((4-isopropil-2-oxazolinyl) (Pr-Pybox) y los ligandos trianiónicos tris-β-diketonato (THP) con Eu (III) y Tb (III).
- Caracterización estructural a través de la cristalografía de rayos X.
- Caracterización fotofísica que incluye mediciones de luminiscencia y polarización circular (CPL).
Principales resultados:
- Formación exitosa de helicatos circulares octanucleares enantiopuros (R y S) con una arquitectura antiprisma cuadrada.
- Los helicatos EuIII y TbIII muestran una luminiscencia f-f característica después de la excitación del ligando.
- Su rendimiento cuántico de emisión es alto (EuIII: 0,145, TbIII: 0,0013 en cloroformo) y su actividad CPL es significativa (de hasta 1,25 para EuIII).
Conclusiones:
- El diseño del ligando permite la formación de helicatos circulares octanucleares quirales bien definidos.
- Estos helicatos exhiben una luminiscencia eficiente y una fuerte CPL, lo que demuestra el potencial para aplicaciones fotónicas quirales.
- Las diferencias de intensidad CPL observadas destacan su utilidad en el desarrollo de dispositivos avanzados de emisión de luz polarizada circular.
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