[PCG23-P01] Infrared spectrum of planetary-nebula analyzed by pure-carbon graphene molecule
Keywords:planetary nebula, graphene, infrared spectrum
We tried the quantum chemical calculation starting from model molecule of (C24) having seven carbon-hexagons using the Gaussian09 program. We applied two astrophysical conditions. One is a void creation by high speed proton, another photo-ionization by the central star. Best calculated result was obtained by graphene (C23) molecule having one carbon pentagon combined with six hexagons. Ionized states were sum of neutral, mono- and di-cations.
By an astronomical observation, we can see 16 infrared bands in a wavelength range of 5~25 micrometer . Experimentally confirmed bands of fullerene (sum of C60 and C70) were 8 bands, half numbers of observed bands. In case of graphene (C23), calculated result shows that all of observed 16 bands can be reproduced very well by this calculation . The reason may be high productivity of graphene from carbon gas as reported from laboratory experiments. We can suggest that graphene plays an important role in the atmosphere of the carbon-star.
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