Quantum studies of acetylene adsorption on ice surface

The interaction of acetylene with the surface of ice was investigated using two quantum ab initio methods. The adsorption energies were calculated wit h the periodic Hartree-Fock method. It was found that the acetylene molecul e is hydrogen bonded to the surface and acts as a proton acceptor. The clus ter Hartree-Fock method was applied in order to calculate the vibrational f requency shifts induced by this adsorption process. The theoretical values were compared to the experimental results and proved instrumental in explai ning the observed spectra, whereas the dimer H2O-C2H2 data (experimental an d theoretical) failed in this interpretation. This paper includes a discuss ion on how to interpret the failure of the dimer model compared to the peri odic model.