An interaction model for $OH+H2O$-mixed and pure $H2O$ overlayers adsorbed on Pt(111) Available to Purchase

A model potential for the adsorbate–adsorbate interaction among OH and $H2O$ molecules adsorbed on a Pt(111) surface has been developed solely based on first-principle calculations. By combining this directional-dependent model potential for the lateral interaction with a lattice model of Ising type, large length scale structure calculations can be made. The strength of different hydrogen bonds can be analyzed in detail from this model potential. It is found that the hydrogen bond between OH and $H2O$ molecules is stronger than that between two $H2O$ molecules (0.4 eV per pair as compared to 0.2 eV per pair, respectively). Via the computed chemical potential for water in mixed $OH+H2O$ overlayers the water uptake as a function of oxygen precoverage on Pt(111) has been determined. The results compare very well with recent experiments.