Acid Enriched with Methanol: Formation of a Prebiotic Cluster in the Interstellar Medium

Organic molecules are a potential source of prebiotic chemistry in the interstellar medium (ISM). Methanol (MetOH) is a very important source of more complex molecules. H₃ O⁺ (aq) and Cl^- (aq) are fundamental to living organisms and can be generated in the ISM from the dissociation of HCl with just four water molecules, yielding the (H₃ O)⁺ (H₂ O)₃ Cl^- ion-pair. Here, a detailed mechanism, based on density functional theory (DFT) and ab-initio (2^nd order Mϕller-Plesset perturbation theory, MP2) calculations, is suggested for the substitution reactions of these water molecules by MetOH. The time required for formation of an appreciable amount of the product ((H₃ O)⁺ (MetOH)₃ Cl^- ) can be only few years. Such reaction can take place in Sagittarius B2, where HCl, H₂ O and MetOH have already been identified and it can be an important source for the formation of more complex prebiotic structures.