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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
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La nucleación fotoinducida del vapor de agua
Science (New York, N.Y.)
|May 19, 1978
Resumen
La nucleación fotoinducida de vapor de agua puro ocurre en longitudes de onda inesperadas. Este proceso es impulsado por grupos de moléculas de agua fotoexcitados, revelando un nuevo mecanismo de nucleación.
Área de la Ciencia:
- Química Física es la química física.
- Ciencias de la atmósfera Ciencias atmosféricas.
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- La nucleación del vapor de agua es crucial para la formación de nubes y los procesos de aerosol.
- La comprensión previa sugería que la luz ultravioleta era necesaria para la nucleación fotoinducida.
- El papel de la luz en la iniciación de la nucleación en condiciones no UV no se había explorado.
Objetivo del estudio:
- Para investigar la nucleación fotoinducida del vapor de agua puro.
- Para explorar la nucleación en rangos de longitud de onda sin absorción ultravioleta reportada por el agua.
- Para dilucidar el mecanismo que impulsa la nucleación de agua inducida por la luz.
Principales métodos:
- Estudios sistemáticos de la velocidad de nucleación y el tiempo de retraso.
- Variar la intensidad de la luz para determinar su efecto en la nucleación.
- Modelado fenomenológico para adaptarse a las observaciones experimentales.
Principales resultados:
- Fuerte nucleación fotoinducida observada en un nuevo rango de longitudes de onda.
- La velocidad de nucleación y el tiempo de retraso mostraron una clara dependencia de la intensidad de la luz.
- Datos experimentales ajustados con precisión por un modelo que involucra grupos de moléculas de agua fotoexcitadas.
Conclusiones:
- El vapor de agua pura puede nuclearse bajo iluminación sin absorción directa de rayos UV.
- La nucleación es iniciada por grupos de moléculas de agua fotoexcitadas.
- Se ha propuesto un nuevo mecanismo fenomenológico para la nucleación fotoinducida.
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