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Cajas de porfirina construidas por ensamblaje auto-clasificador homoquiral: separación óptica, acoplamiento de
In-Wook Hwang1, Taisuke Kamada, Tae Kyu Ahn
1Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea.
Journal of the American Chemical Society
|December 9, 2004
Resumen
Las cajas de porfirina (Bn) autoensambladas de zinc (II) se forman a través de la autoclasificación homoquiral. Estas estructuras facilitan la migración eficiente de la energía de excitación, imitando los complejos naturales de recolección de luz.
Área de la Ciencia:
- Química supramolecular de las moléculas.
- La fotoquímica es la fotoquímica.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Meso-piridina-apegado zinc ((II) porfirinas (Mn) y sus dímeros (Dn) auto-ensamblado.
- Los cuadrados de porfirina tetramérica (Sn) y las cajas (Bn) se forman espontáneamente en disolventes no coordinados.
Objetivo del estudio:
- Investigar el ensamblaje homoquiral de autoclasificación de las cajas de porfirina (Bn).
- Caracteriza la migración de la energía de excitación dentro de estas estructuras autoensambladas.
- Modela complejos de recolección de luz utilizando cajas de porfirina.
Principales métodos:
- Separación óptica y espectroscopia de dicroísmo circular (CD).
- Espectroscopia de absorción transitorio de femtosegundo.
- Mediciones de anisotropía de polarización y modelo de salto de energía tipo Förster.
Principales resultados:
- Se confirmó el ensamblaje homoquiral de autoclasificación de las cajas de porfirina (Bn).
- Se observaron acoplamiento de excitación y migración de energía dentro de Bn.
- Las tasas de salto de energía de excitación se cuantificaron para B1, B2 y B3.
Conclusiones:
- Las cajas de porfirina autoensambladas (Bn) proporcionan un sistema de modelo 3D bien definido.
- Estas estructuras imitan efectivamente la función de los complejos de recolección de luz natural.
- El estudio aclara los mecanismos de transferencia de energía en los sistemas de fotosíntesis artificial.
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