Interstellar branched chain molecules: A theoretical-rotational study

Abstract

Interstellar detection of the straight-chain (n-propyl cyanide, n-C3H7CN) and branched-chain (i-propyl cyanide, i-C3H7CN) molecules toward the star-forming region, Sagittarius B2(N2) (Sgr B2(N2)) has attracted attention to study the formation mechanism and chemical evolution of branched carbon-chain molecules. These molecules are the precursors of biologically relevant prebiotic molecules, i.e., amino acids. In this light, we consider n-butyl cyanide and higher-order branched chain molecule, t-butyl cyanide from the C5H9N isomeric group. Quantum chemical calculations, such as rotational constants, dipole moments and other spectroscopic information will assist to study the chemical evolution and examine the possibility of detecting higher-order branched-chain molecules in high-mass star-forming regions. © 2023, Indian Academy of Sciences.