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Reducción de dinitrógeno a través de la activación fotoquímica de los complejos de tierras raras heteroelépticos tris
Megan E Fieser1, Jefferson E Bates, Joseph W Ziller
1Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|February 26, 2013
Resumen
Los complejos de tierras raras se someten a una reducción fotoquímica del dinitrógeno (N2) para formar productos de nitruro. Este proceso es impulsado por la absorción de luz dentro de la estructura del ligando, revelando una nueva fotoquímica de tierras raras.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La fotoquímica es la fotoquímica.
- Química de las tierras raras.
Sus antecedentes:
- El dinitrógeno (N2) es una molécula estable, y su reducción es crucial para muchos procesos industriales y biológicos.
- Los elementos de tierras raras exhiben propiedades electrónicas únicas que pueden aprovecharse para aplicaciones catalíticas.
Objetivo del estudio:
- Para investigar la reducción fotoquímica del dinitrógeno utilizando complejos de tierras raras.
- Para explorar el mecanismo de esta inusual fotoquímica de las tierras raras.
Principales métodos:
- Síntesis de complejos de tierras raras mixtos-ligando tris ((cyclopentadienyl). complejos de tierras raras.
- Experimentos de activación fotoquímica. experimentaciones de activación fotoquímica.
- Cálculos de la teoría funcional de la densidad (DFT).
Principales resultados:
- La reducción de dinitrógeno se logró a través de la activación fotoquímica de complejos de tierras raras.
- Se formaron los productos [(C5Me4R) 2Ln]2 ((μ-η(2):η(2)-N2, lo que indica la reducción de N2 a (NN) (((2-) y la oxidación del ligando.
- Los cálculos de DFT sugieren que las absorciones basadas en ligandos racionalizan la fotoquímica observada.
Conclusiones:
- Los complejos de tierras raras pueden mediar la reducción fotoquímica del dinitrógeno.
- El mecanismo involucra fotoexcitaciones centradas en los ligandos.
- Este estudio abre nuevas vías para la activación del dinitrógeno utilizando la fotoquímica.
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