Effect of hydrogen-bonded interactions on the energetics and spectral properties of the astromolecule aminoacetonitrile

A detailed and systematic electronic structure calculation has been performed to analyze the hydrogen-bonded interaction of aminoacetonitrile (H2NCH2CN) with hydrogen cyanide (HCN) and Glycine (H2NCH2COOH). Both HCN and aminoacetonitrile have already been detected in the interstellar medium (ISM) and their active role in the molecular mechanisms of glycine production has already been recognized. Four different density functional models have been used to study the effect of hydrogen bond formation on the energetic stability and vibrational spectra of the aminoacetonitrile-HCN and aminoacetonitrile-glycine complexes in gas phase. The aminoacetonitrile-glycine dimer is energetically far more stable than all forms of aminoacetonitrile-HCN dimers. Elastic and inelastic scattering of light off the hydrogen-bonded clusters have been investigated in details via Rayleigh and Raman spectroscopic parameters. The dipole moments and depolarization ratios are found to be sensitive on the type of hydrogen-bond network. The mean polarizabilty show appreciable dependence on the choice of the DFT-model. In general, all the chemical groups (OH, CN, NH2, and CH) that participate directly in the hydrogen bond formation suffer appreciable variation in the intensity of vibration.