Gas phase formation of carbon cluster (fullerenes and graphenes)/prebiotic sugar complexes.

Abstract

Among the constituent molecular classes of proteins and nucleic acids, the presence of Ribose and deoxy-Ribose in space remains unclear. Here, we provide experimental evidence of astronomically related sugar derivatives - carbon cluster (fullerenes and graphenes)/prebiotic sugar complexes - and study their formation processes in the gas phase. The results show that, with PAH cations (dicoronylene, DC, C48H20+)/(2-deoxy-d-Ribose, dR, C5H10O4, and dehydrated 2-deoxy-d-Ribose, DedR, C5H8O3) and fullerene cations (C60+)/(dR and DedR) as the initial molecular precursors, two series of graphene-prebiotic sugar cluster cations (graphene/dR and graphene/DedR, e.g., (dR)Cn+ and (DedR)Cn+) and two series of fullerene-prebiotic sugar cluster cations (fullerene/dR and fullerene/DedR, e.g., (dR)(DedR)2Cn+, (DedR)3Cn+, and (dR)2(DedR)Cn+) are formed through an ion-molecule reaction pathway under the influence of a strong radiation field. The structures of the newly formed complexes and the binding energies of these formation reactions are initially theoretically calculated. These laboratory studies attest to the importance of ion-molecule reaction synthesis routes for the chemical complexity in space, demonstrating that the gas phase interstellar materials could directly lead to the formation of large and complex sugar derivatives in a bottom-up growth process. The chemical evolution in space in which single molecules are transformed into complex molecules produces a wide variety of organic compounds (e.g., carbon cluster (fullerenes and graphenes)/prebiotic sugar complexes). For their astrobiological implications, this opens up aromatic based biogenic chemistry that is available to the parent of PAHs or fullerenes in the interstellar environments.