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Química interestelar: una estrategia para detectar hidrocarburos aromáticos policíclicos en el espacio
F J Lovas1, Robert J McMahon, Jens-Uwe Grabow
1Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Journal of the American Chemical Society
|March 24, 2005
Resumen
Los hidrocarburos aromáticos policíclicos polares (HAP) como el corannuleno son clave para confirmar los HAP en el espacio. La espectroscopia de microondas midió el momento dipolo del corannuleno, lo que permitió la identificación radioastronómica de estas moléculas interestelares cruciales.
Área de la Ciencia:
- La astroquímica es astroquímica.
- La radioastronomía es una radioastronomía.
- La espectroscopia es una técnica de espectroscopia.
Sus antecedentes:
- Se sospecha que los hidrocarburos aromáticos policíclicos (HAP) son moléculas interestelares.
- Los espectros infrarrojos sugieren la presencia de HAP, pero la identificación por radio es difícil debido a los momentos dipolo bajos.
Objetivo del estudio:
- Para permitir la identificación radioastronómica definitiva de los HAP en el espacio.
- Para investigar los HAP polares, como el corannuleno, como posibles objetivos radioastronómicos.
- Para obtener información sobre la química del medio interestelar.
Principales métodos:
- Adquisición del espectro rotacional de alta resolución del corannuleno utilizando la espectroscopia de microondas de la transformada de Fourier.
- Medición del momento dipolo del corannuleno a través del efecto Stark.
Principales resultados:
- Se obtuvo con éxito el espectro de rotación del corannuleno.
- Se midió un momento dipolo significativo de 2,07 D para el corannuleno.
- Esta medición confirma el corannuleno como un HAP polar adecuado para la radioastronomía.
Conclusiones:
- Los HAP polares, ejemplificados por el corannuleno, son objetivos viables para la detección radioastronómica.
- El momento dipolar medido del corannuleno facilita su identificación en entornos interestelares y circumestelares.
- Este trabajo avanza en la confirmación de los HAP en el espacio y la comprensión de la astroquímica.
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