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Acceso al estado excitado triple en perylenediimides
Aaron A Rachford1, Sébastien Goeb, Felix N Castellano
1Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
Journal of the American Chemical Society
|February 14, 2008
Resumen
Los investigadores desarrollaron nuevos complejos de platino (II) con fracciones de PDI, accediendo al colector triple de PDI manteniendo las propiedades del tinte. Estos complejos muestran fluorescencia apagada y exhiben distintas vidas de estado triple.
Área de la Ciencia:
- Coordinación Química de la Coordinación
- La fotofísica es la fotofísica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los tintes de perileno diimida (PDI) son conocidos por su excelente resistencia al color y absorción de luz.
- El acceso al estado triple de PDI es crucial para aplicaciones como la terapia fotodinámica y la electrónica orgánica.
- Los métodos anteriores a menudo comprometían las propiedades deseables de los tintes PDI.
Objetivo del estudio:
- Para sintetizar nuevos complejos de platino (II) que incorporan fracciones de PDI.
- Para investigar las propiedades fotofísicas de estos complejos Pt(II) -PDI, centrándose en el acceso al estado triple.
- Para preservar la resistencia al color y las características de absorción de luz inherentes a los tintes PDI.
Principales métodos:
- Síntesis y caracterización estructural de tres nuevos complejos Pt(II) con unidades PDI conectadas a través de puentes de acetiluros.
- Fotólisis de flash láser de nanosegundos para estudiar la dinámica del estado excitado.
- Experimentos de sensibilización en el estado triple con tioxantona.
Principales resultados:
- Se sintetizaron y caracterizaron con éxito los complejos Pt (II) -PDI.
- La fluorescencia de estado único de PDI se apagó cuantitativamente tras la ligadura a Pt (II).
- Los espectros de absorción transitorios fueron similares en todos los complejos, con distintas vidas de tripletes de un solo exponencial (246 ns, 1,0 μs, 710 ns).
- Las asignaciones de estados triplet se confirmaron a través de experimentos de sensibilización.
Conclusiones:
- Se estableció una estrategia para acceder al colector triple de PDI en los complejos Pt (II).
- Los complejos sintetizados mantienen las propiedades deseables del tinte PDI.
- El estudio proporciona información sobre la fotofísica de los sistemas Pt(II) -PDI para aplicaciones potenciales.
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