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Dos de las propiedades de absorción de fotones de los derivados del 1,3,5-triciano-2,4,6-tris(estirilo) benceno
1Molecular Opto-Electronics Laboratory, Department of Chemistry and Center for Electro- & Photo-Responsive Molecules, Korea University, 1-Anamdong, Seoul 136-701, Korea.
Journal of the American Chemical Society
|October 11, 2001
Resumen
Los investigadores investigaron la absorción de dos fotones (TPA) en los nuevos derivados del benceno. Descubrieron que el aumento de la longitud de conjugación y la fuerza del donante mejora las propiedades del TPA, ofreciendo una estrategia para diseñar nuevos tintes TPA.
Área de la Ciencia:
- La óptica no lineal es la óptica no lineal.
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
Sus antecedentes:
- La absorción de dos fotones (TPA) es un proceso óptico no lineal con aplicaciones en microscopía y almacenamiento de datos ópticos.
- Los derivados del benceno con conjugación pi extendida son candidatos prometedores para los materiales de TPA.
Objetivo del estudio:
- Para investigar las propiedades del TPA de los derivados de 1,3,5-triciano-2,4,6-tris(estilo) benceno.
- Comprender la relación entre la estructura molecular y la eficiencia del TPA.
Principales métodos:
- Análisis espectroscópico que incluye espectros de absorción de un fotón, fluorescencia y excitación.
- Medición de la sección transversal del TPA (delta ((max)) utilizando el método de fluorescencia inducida por dos fotones con pulsos de nanosegundos.
Principales resultados:
- Los compuestos exhiben grandes desplazamientos de Stokes que aumentan con la longitud de la conjugación.
- Los espectros de excitación de uno y dos fotones son similares, lo que indica estados excitados compartidos.
- Los valores máximos de la sección transversal de TPA oscilan entre (50-2620) x 10(-50) cm4 s/fotón.
- La eficiencia del TPA aumenta con la fuerza del donante y la longitud de la conjugación.
Conclusiones:
- Existe una relación lineal entre delta (max) y beta (hiperpolarizabilidad).
- Esta relación delta-beta proporciona una estrategia sintética valiosa para el diseño de nuevos tintes TPA octupolares.
- Los compuestos estudiados demuestran un potencial significativo para aplicaciones de TPA.
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