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Mono-, di- y Ttianionic ligandos beta-diketiminato: un estudio computacional y la síntesis y estructura de [(YbL)
Odile Eisenstein1, Peter B Hitchcock, Alexei V Khvostov
1LSDSMS (UMR 5636), Université Montpellier 2, 34095, Montpellier Cedex 5, France.
Journal of the American Chemical Society
|September 4, 2003
Resumen
Los investigadores sintetizaron un nuevo grupo trinuclear de itérbio (Yb) con estados de oxidación mixtos Yb(II) / Yb(III). Este cúmulo es este grupo.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Coordinación Química de la Coordinación
- Química de los Lantánidos
Sus antecedentes:
- Son de interés los complejos de iterbio con ligandos beta-diketiminados.
- Comprender la estructura electrónica de los grupos de lantánidos de valencia mixta es un desafío.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo cúmulo de itérbio trinuclear con estados de oxidación mixtos Yb(II) e Yb(III).
- Para investigar la distribución de electrones dentro de este cúmulo y un complejo relacionado Yb (II) complejo.
Principales métodos:
- Síntesis de un grupo trinuclear Yb [(YbL) 3 ((THF) ] (1) utilizando [YbL2] y Yb-naftaleno.
- Caracterización por cristalografía de rayos X. Caracterización por cristalografía de rayos X.
- Análisis computacional utilizando cálculos de la Teoría Funcional de la Densidad (DFT) y de la ONIOM (Mecánica Cuántica/Mecánica Molecular).
Principales resultados:
- Se sintetizó y caracterizó con éxito un nuevo cúmulo trinuclear Yb (1) que contiene tanto centros Yb (II) como Yb (III).
- La cristalografía de rayos X confirmó la estructura del cúmulo.
- Los cálculos de DFT y ONIOM proporcionaron información sobre la distribución de electrones dentro del grupo 1 y un complejo Yb (II) (2).
Conclusiones:
- El estudio reporta el primer cúmulo trinuclear de Yb con estados de oxidación mixtos Yb (II) / Yb (III).
- El análisis de la estructura electrónica ofrece información valiosa para comprender los sistemas de lantánidos de valencia mixta.
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