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Dinámica de la localización de electrones mediada por disolventes en hexacianoferrato excitado electrónicamente (III)
Wenkai Zhang1, Minbiao Ji, Zheng Sun
1PULSE Institute, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, USA.
Journal of the American Chemical Society
|January 12, 2012
Resumen
Investigamos la localización del agujero de electrones en Fe ((CN) 6 ((3-) excitado utilizando espectroscopia. Inicialmente deslocalizado, el agujero se localiza en un estado excitado secundario, lo que indica un cambio de simetría.
Área de la Ciencia:
- La fotoquímica es la fotoquímica.
- La espectroscopia es una técnica de espectroscopia.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
Sus antecedentes:
- La excitación de transferencia de carga de ligando a metal (LMCT) es crucial en los complejos de metales de transición.
- Comprender la dinámica del estado excitado, incluyendo la localización del agujero de electrones, es clave para controlar la reactividad.
Objetivo del estudio:
- Para investigar la dinámica de la localización del agujero de electrones en el estado excitado Fe(CN)6(3-) después de la excitación LMCT.
- Para determinar la simetría y la naturaleza de los estados excitados involucrados.
Principales métodos:
- Se empleó la espectroscopia de sonda de bomba UV-medio-IR con resolución de polarización.
- Se realizó un análisis de las bandas de absorción de estiramiento CN y su anisotropía.
Principales resultados:
- El estado excitado inicial del LMCT exhibe una única banda de estiramiento CN sin anisotropía, lo que indica un agujero del ligando deslocalizado y una simetría octaédrica preservada.
- Se observó un estado excitado secundario con dos bandas de estiramiento CN, lo que significa simetría inferior.
- La formación del estado secundario es dependiente del disolvente.
Conclusiones:
- El orificio del ligando deslocalizado inicialmente se localiza en el estado excitado secundario.
- Esta localización lleva a una pérdida de la simetría octaédrica.
- Los hallazgos proporcionan información sobre la dinámica del estado excitado y la ruptura de simetría en los complejos de metales de transición.
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