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El empaquetado ineficiente de cristales en quiral [Ru(phen)(3)](PF(6))(2) permite el apagado de moléculas de oxígeno
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|January 22, 2009
Resumen
Los cristales puros de rutenio quiral ((II) tris ((1,10-fenantrolina) hexafluorofosfato muestran un apagado significativo de la emisión de oxígeno debido a sus estructuras abiertas. Los cristales racemicos exhiben un apagado mínimo, destacando los impactos estructurales en la luminiscencia.
Área de la Ciencia:
- La fotoquímica es la fotoquímica.
- Química del estado sólido.
- La luminiscencia es la luminiscencia.
Sus antecedentes:
- Los complejos de polipiridil de rutenio ((II) son conocidos por sus propiedades fotoluminiscentes.
- Las propiedades de emisión del estado sólido pueden ser influenciadas por el envasado de cristales y las moléculas invitadas.
- El oxígeno es un conocido extinguidor de la luminiscencia.
Objetivo del estudio:
- Investigar el efecto del oxígeno molecular en la emisión en estado sólido de cristales quirales y racémicos de tris{1,10-fenantrolina) rutenio{II) hexafluorofosfato.
- Para correlacionar el comportamiento de apagado de emisiones con la estructura cristalina y el empaque.
Principales métodos:
- La espectroscopia de emisión es una técnica de espectroscopia de emisión.
- Mediciones a lo largo de la vida útil.
- Análisis gravimétrico térmico (TGA)
- Un solo cristal de difracción de rayos X de un solo cristal.
Principales resultados:
- Los enantiómeros puros (Delta y Lambda) de Ru(phen) 3(PF6) 2 exhibieron un apagado de emisión significativo y similar por el oxígeno (0.36(2) y 0.33(2)).
- La mezcla racémica de Ru (((phen) 3 (((PF6) 2 mostró una disminución sustancial de la extinción del oxígeno (0,05 (((2)).
- Los cristales quirales poseen canales abiertos que facilitan la difusión de oxígeno, a diferencia de los cristales racémicos densamente empacados.
Conclusiones:
- La estructura cristalina tiene un impacto significativo en el apagado de oxígeno de la emisión en estado sólido en Ru(phen) 3(PF6) 2.2.
- Los canales de cristal abierto en formas quirales permiten un apagado eficiente de la luminiscencia mediante la difusión de oxígeno.
- El apagado de la luminiscencia es menos efectivo en cristales racémicos debido a su estructura compacta.
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