A theoretical investigation of the possible detection of C₂₄ in space

Abstract

Astronomical infrared spectral features at ∼6.6, 9.8 and 20 µm have recently been suggested as being due to the planar graphene form of C₂₄ carbon cluster. Here, we report density functional theory and coupled cluster calculations on wavefunctions stability, relative energies and infrared spectra of four different types of C₂₄ isomers, including the graphene and fullerene forms. The types of vibrational motions under these bands are also discussed. Among the four isomers, we find that the astronomical data are best approximated by the graphene form of C₂₄.

Keywords:

• C₂₄
• graphene
• interstellar media
• CCSD(T)

Additional information

Funding

The Laboratory for Space Research was established by a special grant from the University Development Fund of the University of Hong Kong. This work is also in part supported by a grant to SK from the Natural Sciences and Engineering Research Council of Canada. DAGH, AM and FC acknowledge support from the State Research Agency (AEI) of the Spanish Ministry of Science, Innovation and Universities (MCIU) and the European Regional Development Fund (FEDER) under grant AYA2017-88254-P.