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We analyze the 11.2 {\mu}m unidentified infrared band (UIR) spectrum from NGC7027 and identify a small fullerene (C24) as a plausible carrier. The blurringeffects of lifetime and vibrational anharmonicity broadening obscure thenarrower, intrinsic spectral profiles of the UIR band carriers. We use aspectral deconvolution algorithm to remove the blurring, in order to retrievethe intrinsic profile of the UIR band. The shape of the intrinsic profile, asharp blue peak and an extended red tail, suggests that the UIR band originatesfrom a molecular vibration-rotation band with a blue band head. The fractionalarea of the band-head feature indicates a spheroidal molecule, implying anon-polar molecule and precluding rotational emission. Its rotationaltemperature should be well approximated by that measured for non-polarmolecular hydrogen, ~825 K for NGC 7027. Using this temperature, and theinferred spherical symmetry, we perform a spectral fit to the intrinsic profilethat results in a rotational constant implying C24 as the carrier. We show thatthe spectroscopic parameters derived for NGC 7027 are consistent with the 11.2{\mu}m UIR bands observed for other objects. We present density functionaltheory (DFT) calculations for the frequencies and infrared intensities of C24.The DFT results are used to predict a spectral energy distribution (SED)originating from absorption of a 5 eV photon, and characterized by an effectivevibrational temperature of 930 K. The C24 SED is consistent with the entire UIRspectrum and is the dominant contributor to the 11.2 and 12.7 {\mu}m bands.

A Small Fullerene (C24) may be the Carrier of the 11.2 micron Unidentified Infrared Band