Model study of H-bonded ROH…(NH3)5 clusters: a search for possible ground-state proton transfer species

Model studies have been made of the non-transferred (reactant) and proton-transferred (product) species of the ground-state hydrogen-bonded clusters ROH…(NH3)5, where ROH is an aromatic alcohol. The structure, relative energies and vibrational frequencies of this species were obtained at the HF/6-31G∗ level of theory. It was found that proton transfer can proceed in the case of phenols with the electron-withdrawing substituents. A low-frequency vibration, which corresponds to the synchronous motion of the solvation shell, does exist in these clusters. The energy of the lowest ππ∗ transition is calculated for aromatic alcohols and their anions at the CASPT2 level with a VDZ basis set.