Astrochemical Significance of CHNO Isomers: A Computational Perspective on Their Stability and Detectability.

Nitrogen- and oxygen-containing molecules play a key role in interstellar chemistry, particularly as precursors to biologically relevant species such as amino acids. Among the CHNO isomers, 2-aminoethanol is the only one detected in the ISM. This study systematically explores the CHNO chemical space, identifying eight structural isomers, with 1-aminoethanol as the global minimum and methylaminomethanol, 11.5 kcal/mol higher in energy, as a viable higher-energy species. To assess their astrochemical relevance, we conducted a comprehensive conformational analysis and computed rotational constants to guide future spectroscopic searches. These findings provide critical insights into CHNO isomers, identifying new candidates for ISM detection and expanding our understanding of nitrogen- and oxygen-containing organic species in space.