Ab initio molecular dynamics calculations of H2O on BaO(001)

Journal article, 2008

Density functional theory calculations are used to explore water adsorption on BaO(001). The stable configuration is found to be a novel hydroxide pair. A detailed analysis demonstrates that the electrostatic repulsion between the OH− species is screened by Ba2+ cations and that the net interaction is provided by hydrogen bonding. Ab initio molecular dynamics at low coverage reveals that the pair is stable at elevated temperatures. The large structural flexibility of the hydoxylated surface may, however, lead to pair dissociation at high coverage. Simulations of a mixed (H2O+OH) overlayer uncover proton transfer between H2O and OH groups.