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Cambio fotoinducido reversible en el ordenamiento molecular de los derivados de diarileteno en una interfaz
Ryota Arai1, Shinobu Uemura, Masahiro Irie
1Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Journal of the American Chemical Society
|June 28, 2008
Resumen
Las moléculas diarylethene-pyrene fotocrómicas cambian su ordenamiento bidimensional en las interfaces. Este ordenamiento molecular es reversible y depende de la estructura molecular específica y la luz.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química supramolecular de las moléculas.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los derivados de diarileteno y pireno son moléculas fotocrómicas con aplicaciones potenciales en interruptores moleculares y almacenamiento de datos.
- Controlar el ordenamiento molecular en las interfaces es crucial para el desarrollo de materiales funcionales avanzados.
Objetivo del estudio:
- Para investigar los cambios fotoinducidos en el ordenamiento molecular bidimensional de los conjugados diarileto-pireno en una interfaz de grafito pirolítico altamente orientado a la solución (HOPG).
- Comprender la relación entre la estructura molecular y el comportamiento de orden observado.
Principales métodos:
- Síntesis de las moléculas diarylethene-pyrene diad y triada.
- Caracterización de los arreglos moleculares en la interfaz solución-HOPG utilizando microscopía de túnel de barrido (STM).
- Análisis del ordenamiento dependiente de isómeros fotocrómicos.
Principales resultados:
- Las moléculas de diarileno-pireno diad y triada exhiben distintos ordenamientos bidimensionales en la interfaz solución-HOPG.
- El ordenamiento de la molécula de la tríada cambia de manera reversible al alternar la irradiación UV y la luz visible.
- Los cambios de ordenamiento fotoinducidos observados se atribuyen a las distintas estructuras moleculares de los isómeros abiertos y cerrados.
Conclusiones:
- El estudio demuestra el control fotoinducido y reversible sobre el ordenamiento molecular en las interfaces utilizando conjugados diarileteno-pireno.
- La estructura molecular juega un papel crítico en dictar el comportamiento de ordenamiento bidimensional.
- Estos hallazgos contribuyen al diseño de conjuntos supramoleculares fotorresponsivos.
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