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Oligómeros conjugados apilados como modelos moleculares para examinar las interacciones entre cadenas en materiales
Kurt M Knoblock1, Catherine J Silvestri, David M Collard
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
Journal of the American Chemical Society
|October 19, 2006
Resumen
Este estudio modela polarones y bipolarones en polímeros conjugados mediante el apilamiento de oligotiofenos. El apilamiento de pi intermolecular tiene un impacto significativo en la estructura electrónica de estos estados redox.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química orgánica es la química orgánica.
- Química Física es la química física.
Sus antecedentes:
- Comprender los polarones y bipolarones en polímeros conjugados es crucial para las aplicaciones electrónicas.
- Los modelos anteriores a menudo descuidan las interacciones intermoleculares en sistemas conjugados de estado sólido.
Objetivo del estudio:
- Investigar la influencia de las interacciones intermoleculares en la estructura electrónica de los oligómeros conjugados.
- Desarrollar modelos robustos para polarones y bipolarones en polímeros conjugados p-dopados.
Principales métodos:
- Oligotiofenos fusionados sintetizados en un núcleo bicyclo [4.4.1]undecane para hacer cumplir el apilamiento cofacial.
- Se realizó la oxidación de uno y dos electrones de los oligómeros apilados.
Principales resultados:
- Se logró el apilamiento cofacial permanente de oligómeros conjugados.
- Generación de cationes y dicationes mono- y radicales estables como modelos para polarones y bipolarones.
- Demostró el efecto significativo del pi-stacking en la estructura electrónica de las especies oxidadas.
Conclusiones:
- El apilamiento pi intermolecular influye profundamente en las propiedades electrónicas de los estados redox en sistemas conjugados.
- Este estudio proporciona un valioso modelo de estado sólido para polarones y bipolarones en polímeros p-dopados.
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