The mechanism determination of trimer and tetramer HCN for adenine formation in the gas phase of interstellar space

Abstract

Trimer and tetramer of HCN are quite important for adenine formation in the oligomerization process, and at this end, the mechanism formation of these species are determinates in the gas phase, by using density functional theory (DFT) method at the B3LYP hybrid together with 6-311g(d,p) basis set level. The mechanisms considered for the isomerization pathway from three and four HCN isomer show that the aminonomalodinitrile (AMDN) and aminoimidazole carbonitrile (AICN) are the most probable and stable trimer and tetramer respectively, because they pass through the smallest barrier energy pathway. Consequently, these products are energetically and kinetically most favourable, under isolated conditions, for the prebiotic syntheses of adenine by oligomerization process under interstellar conditions.