UNIDENTIFIED INFRARED EMISSION BANDS: PAHs or MAONs?

2013/04/29 by Sun Kwok, Yong Zhang · 6 citations
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Amorphous solid #Analytical Chemistry (journal) #Astrophysics and Star Formation Studies #Chemistry #Gas phase #Hydrocarbon #Infrared #Infrared spectroscopy #Materials science #Molecular Spectroscopy and Structure #Molecule #Optics #Organic chemistry #Phase (matter) #Photochemistry #Physical chemistry #Physics #Polycyclic aromatic hydrocarbon #Solid-state #astro-ph.GA

paper · pdf · doi:10.1088/0004-637x/771/1/5

9 figures, accepted for publication in The Astrophysical Journal

arxiv created 2013/04/29 · openalex publication_date 2013/06/07 · arxiv updated 2015/06/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We suggest that the carrier of the unidentified infrared emission (UIE) bands is an amorphous carbonaceous solid with mixed aromatic/aliphatic structures, rather than free-flying polycyclic aromatic hydrocarbon molecules. Through spectral fittings of the astronomical spectra of the UIE bands, we show that a significant amount of the energy is emitted by the aliphatic component, implying that aliphatic groups are an essential part of the chemical structure. Arguments in favor of an amorphous, solid-state structure rather than a gas-phase molecule as a carrier of the UIE are also presented.

Citations

• Unidentified infrared bands in the interstellar medium across the Galaxy
• Infrared Emission from Interstellar Dust. II. The Diffuse Interstellar Medium
• Mixed aromatic–aliphatic organic nanoparticles as carriers of unidentified infrared emission features

Cited by

• Restructuring and destruction of hydrocarbon dust in the interstellar medium
• Particle Dark Matter Searches Outside the Local Group
• Rotational spectroscopy of interstellar PAHs
• Search for polycyclic aromatic hydrocarbons in the Perseus molecular cloud with the Green Bank Telescope
• Petroleum, coal and other organics in space
• ON THE VIABILITY OF THE PAH MODEL AS AN EXPLANATION OF THE UNIDENTIFIED INFRARED EMISSION FEATURES

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