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Detección atmosférica de dímeros de agua a través de absorción en el infrarrojo cercano
K Pfeilsticker1, A Lotter, C Peters
1Institut für Umweltphysik, INF 229, University of Heidelberg, D-69120 Heidelberg, Germany.
Science (New York, N.Y.)
|June 28, 2003
Resumen
Los investigadores detectaron dímeros de agua (DV) utilizando espectroscopia de trayectoria larga. Este hallazgo avanza en la comprensión de las WD en la fotoquímica atmosférica y los estudios climáticos.
Área de la Ciencia:
- Química de la atmósfera La química de la atmósfera
- La espectroscopia es una técnica de espectroscopia.
- Física molecular Física molecular La física molecular es la física de las moléculas.
Sus antecedentes:
- Los dímeros de agua (WD) son pares de moléculas de agua débilmente unidas.
- Los WD pueden influir en la fotoquímica y el clima.
- La superposición espectral con los monómeros de agua (WM) dificulta la detección de WD.
Objetivo del estudio:
- Para medir la absorción de agua dimers.
- Para detectar el modo de estiramiento OH, la transición de tono abierto de WDs.
Principales métodos:
- Espectroscopia de absorción óptica diferencial de largo recorrido atmosférico (18,34 km).
- Medición del modo de estiramiento de OH en el infrarrojo cercano. transición de tono abierto.
Principales resultados:
- Banda de absorción WD observada a 749,5 nm. observado en la banda de absorción WD en 749,5 nm. observado en la banda de absorción WD en 749,5 nm. observado en la banda de absorción WD en 749,5 nm.
- La anchura completa en la mitad máxima (FWHM) de aproximadamente 19.4 cm-1.
- La fuerza de la banda se estima entre 1,23 x 10-22 y 5,25 x 10-22 cm / molécula.
Conclusiones:
- Las características espectrales observadas se alinean con las propiedades conocidas de WD.
- Esta detección proporciona datos cruciales para los modelos atmosféricos y climáticos.
- Avanza en la comprensión del papel del dímero de agua en los procesos atmosféricos.
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