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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Identificación espectroscópica de los radicales cis- y trans-1-vinilpropargil estabilizados por resonancia
Neil J Reilly1, Masakazu Nakajima, Tyler P Troy
1School of Chemistry, The University of Sydney, NSW 2006, Australia.
Journal of the American Chemical Society
|September 17, 2009
Resumen
Los radicales cis- y trans-1-vinilpropargil (1VPR) fueron identificados mediante espectroscopia avanzada. Se analizaron sus transiciones electrónicas y su estabilidad, proporcionando información sobre la química radical.
Área de la Ciencia:
- Química Física es la química física.
- La espectroscopia es una técnica de espectroscopia.
- Física Química Física Química es la física de la química.
Sus antecedentes:
- Las especies radicales son intermediarios cruciales en las reacciones químicas.
- Comprender la estructura y la estabilidad de los radicales insaturados es importante para los mecanismos de reacción.
Objetivo del estudio:
- Para identificar y caracterizar los radicales cis- y trans-1-vinilpropargilo (1VPR).
- Para determinar las transiciones de origen electrónico y la estabilidad de estos isómeros.
Principales métodos:
- Producción de radicales en una descarga de hidrocarburos enfriada supersónicamente.
- Identificación mediante espectroscopias bidimensionales de fluorescencia y ionización.
- Análisis apoyado por espectroscopia de fluorescencia dispersa y cálculos computacionales.
Principales resultados:
- Las transiciones de origen electrónico para cis-1VPR y trans-1VPR se identificaron en 21,232 y 21,645 cm.
- Excelente acuerdo entre las frecuencias experimentales y calculadas del estado fundamental y las constantes de rotación.
- Las energías de transición computarizadas coinciden estrechamente con las posiciones de las bandas observadas.
Conclusiones:
- El estudio identificó y caracterizó con éxito los radicales cis y trans-1VPR.
- La mayor estabilización de resonancia de las especies de propargyl sustituidas por 1 explica su abundancia observada en comparación con los análogos sustituidos por 3.
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