Among all existing complex organic molecules, glycolaldehyde HOCH 2 CHO and ethylene glycol HOCH 2 CH 2 OH are two of the largest detected molecules in the interstellar medium. We investigate both experimentally and theoretically the low-temperature reaction pathways leading to glycolaldehyde and ethylene glycol in interstellar grains. Using infrared spectroscopy, mass spectroscopy and quantum calculations, we investigate formation pathways of glycolaldehyde and ethylene glycol based on HCO and CH 2 OH radical-radical recombinations. We also show that CH 2 OH is the main intermediate radical species in the H 2 CO to CH 3 OH hydrogenation processes. We then discuss astrophysical implications of the chemical pathway we propose on the observed gas-phase ethylene glycol and glycolaldehyde.

By means of ab initio quantum chemical techniques, the interaction of molecular hydrogen with the first member of the IRMOF family is explored. Many different models and computational schemes, ranging from second-order Møller−Plesset perturbation theory (MP2) to density functional theory (DFT), have been applied in order to find the best model that can describe the IRMOF-1 cell in an accurate manner against moderate computational cost. The results show that the interaction energies of dihydrogen with the inorganic part of the IRMOF-1 are between 0.13 and 0.74 kcal/mol and can be attributed to dipole−induced dipole forces. Basis-set superposition errors are corrected for by the function counterpoise method. The effect of the corrections is large, almost 50% of the uncorrected interaction energy. Furthermore, the correction may shift the minimum of the potential energy curve toward larger distances. The computational approaches used in this study, allow us to find the true minimum of the potential hypersurface. As a conclusion, both organic and inorganic linkers contribute equally to dihydrogen physisorption.