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Quiralidad inducida por el campo eléctrico en cristales líquidos columnares
Alberto Concellón1, Ru-Qiang Lu1, Kosuke Yoshinaga1
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|June 11, 2021
Resumen
Las nuevas moléculas discóticas de tetrafenilbenceno forman agregados J y fases de cristal líquido. Un campo eléctrico induce la organización helicoidal en estos cristales líquidos quirales (LC), lo que permite nuevos materiales quirales.
Área de la Ciencia:
- Ciencias de los materiales
- Química supramolecular
- Química orgánica
Sus antecedentes:
- Las moléculas discóticas se ensamblan en estructuras ordenadas.
- Los cristales líquidos (LC) exhiben comportamientos de fase únicos.
- Los materiales quirales son cruciales para aplicaciones avanzadas.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevas moléculas discóticas basadas en tetrafenilbenceno.
- Para investigar su auto-ensamblaje y propiedades cristalinas líquidas.
- Para explorar la organización quiral inducida por el campo eléctrico.
Principales métodos:
- Síntesis de moléculas discóticas basadas en tetrafenielbenceno.
- Espectroscopia de absorción y fluorescencia para el estudio de la agregación.
- Microscopía óptica polarizada y calorimetría de barrido diferencial para el análisis de fase LC.
- Aplicación de campos eléctricos para inducir cambios estructurales.
Principales resultados:
- Formación de agregados de tipo J en solución con mayor emisión.
- Observación de las fases de cristales líquidos columnares hexagonales enantiotrópicos.
- Transición inducida por el campo eléctrico a una organización en columnas helicoidales.
- Inducción de quiralidad impulsada por la conformación molecular y los centros estereogénicos.
Conclusiones:
- Las moléculas discóticas de tetrafenilbenceno exhiben un comportamiento de autoensamblaje y LC notables.
- Los campos eléctricos pueden inducir controlablemente la quiralidad helicoidal en fases columnares.
- Estos hallazgos abren caminos para el desarrollo de materiales quirales de próxima generación.
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