Anharmonic Assignment of the Water Octamer Spectrum in the OH Stretch Region

We interface thequasi-classical trajectory approachwith an ab initio potential energy surface for waterto assign thevibrational spectroscopical features of the OH stretch region of thewater octamer cluster, which is considered to be a precursor of ice.An attempt by Li et al. to assign their recent reference experimentinvolved lower-level calculations based on an ad hoc scaled harmonic approach. Differently from the conclusions of thisprevious assignment, which invoked the contribution of 5 conformersand a solvated form of the water heptamer in the spectrum, we findout that the spectroscopic features can be related to the 4 conformersof the octamer lying lower in energy.