Vibrational, Rotational, and Electronic Spectroscopy for Possible Interstellar Detection of AlNH₂ and HAlNH

Abstract We obtained accurate vibrational frequencies, rotational constants, and vertical transition energy for AlNH 2 (X 1 A ) HAlNH(X A′) isomers using ab initio calculations at various levels of theory. These two are potential candidates astronomical observation. HAlNH thermodynamically stable, with Al-NH HAl-NH bond dissociation energies predicted to be 4.39 3.60 eV, respectively. The characterized by sizable dipole moments 1.211 3.64 D, anharmonic frequencies spectroscopic constants reported the should facilitate their experimental differentiation. In addition, we evaluated evolution low-lying electronic states along stretching coordinates, as well absorption cross sections. absorbs strongly around 287, 249, 200 nm, whereas is centered 370 233 nm.