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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Orbitales compartidos: desactivaciones ultrarrápidas en estado excitado con diferentes resultados en los bucky
Dirk M Guldi1, G M Aminur Rahman, Renata Marczak
1Universität Erlangen, Institute for Physical and Theoretical Chemistry, 91058 Erlangen, Germany. dirk.guldi@chemie.uni-erlangen.de
Journal of the American Chemical Society
|July 20, 2006
Resumen
Los conjugados de ferroceno Bucky exhiben una transferencia de carga significativa, formando pares de iones radicales metastables. Los conjugados de rutenoceno Bucky no muestran separación de cargas debido a una desactivación más rápida y potenciales de oxidación desfavorables.
Área de la Ciencia:
- La fotoquímica y la fotofísica.
- Química organometálica Química orgánica de los metales.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los conjugados fullereno-organometálicos son de interés por sus propiedades electrónicas.
- El ferroceno y los derivados del rutenoceno ofrecen características electrónicas y redox distintas.
Objetivo del estudio:
- Para investigar las interacciones electrónicas de estado excitado y de base en los conjugados de bucky ferroceno y bucky rutenoceno.
- Para comparar la dinámica de transferencia de carga y las propiedades fotofísicas entre los sistemas que contienen hierro y rutenio.
Principales métodos:
- Espectroscopia de fluorescencia de estado estacionario y resolución de tiempo.
- Experimentos de bomba-sonda de femtosegundos y nanosegundos en los experimentos de bomba-sonda de femtosegundos y nanosegundos
- La radiólisis por pulso es una radiólisis por pulso.
Principales resultados:
- Los conjugados de ferroceno Bucky muestran un cambio sustancial en la densidad de carga del estado fundamental del ferroceno al fullereno.
- Los estados excitados de los conjugados de ferroceno bucky se someten a una rápida separación de carga (0,8 ps) formando pares de iones radicales con una vida útil de 27-39 ps.
- Los conjugados de rutenoceno Bucky no exhiben separación de carga; en su lugar, se produce una desactivación más rápida del estado excitado (~ 200 ps) debido al centro de rutenio más pesado y al potencial de oxidación desfavorable.
Conclusiones:
- El contacto íntimo en el ferroceno bucky permite una eficiente transferencia de electrones fotoinducida.
- Las propiedades del rutenio, incluida su naturaleza más pesada y su potencial redox, inhiben la separación de cargas en el bucky rutenoceno, lo que lleva a una rápida desactivación.
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