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Updated: Jun 6, 2026
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Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
Inversión de la manualidad reversible impulsada por la luz en superestructuras helicoidales autoorganizadas.
Manoj Mathews1, Rafael S Zola, Shawn Hurley
1Liquid Crystal Institute and Chemical Physics Interdisciplinary Program, Kent State University, Kent, Ohio 44242, USA.
Journal of the American Chemical Society
|December 4, 2010
Resumen
Los investigadores lograron un ajuste de color reversible en cristales líquidos mediante el uso de dopantes quirales sensibles a la luz. Esta conmutación de modo fotónico rápido permite colores de reflexión sintonizables desde el azul hasta el infrarrojo cercano, con potencial para nuevos materiales ópticos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
- La fotónica es la fotónica.
Sus antecedentes:
- Los cristales líquidos colestéricos exhiben superestructuras helicoidales auto-organizadas.
- Los dopantes quirales inducen y controlan las estructuras helicoidales en cristales líquidos.
- Las moléculas fotoisomerizables ofrecen propiedades sintonizables a la luz.
Objetivo del estudio:
- Desarrollar un método de modo fotónico rápido para la inversión reversible de la mano en cristales líquidos colestéricos.
- Para utilizar azobenzenofanos cíclicos quirales fotoisomerizables como dopantes para propiedades ópticas sintonizables.
- Para investigar la inducción de manos helicoidales opuestas utilizando diferentes estados de conmutación de dopante.
Principales métodos:
- Síntesis y caracterización de dos azobenzenofanos cíclicos quirales.
- Incorporación de dopantes en anfitriones de cristales líquidos achirales.
- La fotoisomerización (trans-cis) inducida por la irradiación de luz.
- Determinación directa de las manos helicoidales utilizando un nuevo método.
Principales resultados:
- Los dopantes quirales demostraron una isomerización trans-cis reversible sin racemicidad.
- Se observó una alta potencia de torsión helicoidal y cambios significativos inducidos por la fotoisomerización.
- Se logró una afinación reversible de los colores de reflexión del azul al infrarrojo cercano.
- La mano helicoidal opuesta fue inducida por diferentes estados de conmutación de los dopantes.
Conclusiones:
- Los dopantes cíclicos quirales fotoisomerizables permiten una inversión rápida y reversible de la manualidad en los cristales líquidos colestéricos.
- El ajuste de color inducido por la luz a través de un amplio espectro (azul a casi IR) es factible.
- El método desarrollado permite la determinación inequívoca de la mano helicoidal en las fases colestéricas de tono largo.
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