ABSTRACT The adsorption characteristics of small, partially oxidized hydrocarbons (POHs), such as formaldehyde, methanol, formic acid and acetone molecules at the (0001) face of the proton disordered ice Ih crystal have been studied by computer simulations performed at tropospheric temperatures. In particular, Grand Canonical Monte Carlo calculations have been performed to determine the configurations of the molecules in their adsorption sites, the adsorption energies, the saturation coverage of one monolayer above the ice surface, and the corresponding adsorption isotherms. The results of these simulations are in close agreement with experimental data, and demonstrate that the main driving force for the adsorption of these partially oxidized hydrocarbons on ice is the formation of hydrogen bonds, not only with the water molecules of the ice surface, but also within the adsorbate. Finally, the present studies show that computer simulation is an accurate and useful tool for studying interactions between POHs and ice under tropospheric condition.
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