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arXiv · 1306.2121

Infrared spectroscopy of fullerene C60/anthracene adducts

D. A. Garcia-Hernandez·F. Cataldo·A. Manchado
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Abstract

Recent Spitzer Space Telescope observations of several astrophysical environments such as Planetary Nebulae, Reflection Nebulae, and R Coronae Borealis stars show the simultaneous presence of mid-infrared features attributed to neutral fullerene molecules (i.e., C60) and polycyclic aromatic hydrocarbons (PAHs). If C60 fullerenes and PAHs coexist in fullerene-rich space environments, then C60 may easily form adducts with a number of different PAH molecules; at least with catacondensed PAHs. Here we present the laboratory infrared spectra (~2-25 um) of C60 fullerene and anthracene Dies-Alder mono- and bis-adducts as produced by sonochemical synthesis. We find that C60/anthracene Diels-Alder adducts display spectral features strikingly similar to those from C60 (and C70) fullerenes and other unidentified infrared emission features. Thus, fullerene-adducts - if formed under astrophysical conditions and stable/abundant enough - may contribute to the infrared emission features observed in fullerene-containing circumstellar/interstellar environments.

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D. A. Garcia-Hernandez, F. Cataldo, A. Manchado. 2013-06-10. Infrared spectroscopy of fullerene C60/anthracene adducts. https://doi.org/10.1093/mnras/stt1032

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