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El salto de electrones en diímidos de perileno covalentes y autoensamblados apilados en pi observados por la
Michael J Tauber1, Richard F Kelley, Jovan M Giaimo
1Department of Chemistry and Center for Nanofabrication and Molecular Self-Assembly, Northwestern University, Evanston, IL 60208-3113, USA.
Journal of the American Chemical Society
|February 9, 2006
Resumen
El salto de electrones ocurre en dímeros de perileno bis ((dicarboximida) (PDI), evidenciado por constantes de acoplamiento hiperfino reducidas a la mitad. Esto revela el intercambio de electrones entre los cromóforos PDI reducidos y neutrales en solución.
Área de la Ciencia:
- La electrónica orgánica es la electrónica orgánica.
- La fotofísica es la fotofísica.
- Se trata de una química supramolecular.
Sus antecedentes:
- Los derivados del perileno bis (dicarboximida) (PDI) son semiconductores orgánicos cruciales.
- Comprender el transporte de carga en los agregados PDI es clave para las aplicaciones de dispositivos.
Objetivo del estudio:
- Investigar el intercambio de electrones y los mecanismos de transporte en los aniones radicales PDI.
- Para estudiar la dinámica de electrones en sistemas de PDI enlazados covalentemente y autoensamblados.
Principales métodos:
- Resonancia paramagnética de electrones (EPR) a temperatura ambiente, en la fase de solución.
- Espectroscopia de doble resonancia electrón-nuclear (ENDOR). espectroscopia de doble resonancia electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR). espectroscopia de resonancia doble electrón-nuclear (ENDOR).
- Espectroscopia de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica. espectroscopía de absorción electrónica.
Principales resultados:
- Las constantes de acoplamiento hiperfino se redujeron a la mitad en dímeros PDI en comparación con los monómeros, lo que indica un intercambio completo de electrones.
- Evidencia de salto de electrones en una escala de tiempo mayor a 107 Hz entre cromóforos PDI reducidos y neutros.
- Los datos espectroscópicos confirmaron las interacciones electrónicas en los agregados PDI covalentes y autoensamblados.
Conclusiones:
- El salto de electrones es un importante mecanismo de transporte de carga en los sistemas PDI.
- El intercambio de electrones observado facilita la deslocalización eficiente de la carga en las dimensiones PDI.
- Los estudios de la fase de solución proporcionan información fundamental sobre el comportamiento electrónico de PDI relevante para la electrónica orgánica.
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