title: Influence of hydrogen bonding on the structure of the (001) corundum-water interface. Density functional theory calculations and Monte Carlo simulations.
abstract: Density functional theory calculations and classical Monte Carlo simulations are applied to study the behavior of water in contact with a hydroxylated corundum (001) surface. Using DFT with periodic boundary conditions at T = 0 K, we systematically study the influence of the number of water molecules on the surface geometry and on the structure of the contact water layer. Only little effect of the thickness of the water layer on the geometry of the surface hydroxyl groups is observed. On the other hand, the molecules in the second layer have strong influence on the arrangement of water molecules in direct contact with the solid surface. In order to mimic macroscopic systems at room temperature, we perform inhomogeneous MC simulations of model corundum surface in contact with the water phase modeled by SPC/E model. The water molecules are classified according to their hydrogen-bonded partners into several groups. It is found that the preferential orientation of interfacial water molecules is primarily determined by the type of their hydrogen bonding. The hydroxyl groups at the corundum surface can serve as hydrogen bond donor or acceptor, depending on their orientation. No surface hydroxyls are found to coordinate two water molecules at the same time. On the other hand, water molecules coordinated by two different surface groups appear in MC simulations.
authors.affiliation: ENSTA ParisTech, UCP , 828 Bd des Maréchaux, 91762 Palaiseau Cedex, France.
authors.forename: Jiří
authors.initials: J
authors.lastname: Janeček
authors.forename: Roland R
authors.initials: RR
authors.lastname: Netz
authors.forename: Mathias
authors.initials: M
authors.lastname: Flörsheimer
authors.forename: Reinhardt
authors.initials: R
authors.lastname: Klenze
authors.forename: Bernd
authors.initials: B
authors.lastname: Schimmelpfennig
authors.forename: Robert
authors.initials: R
authors.lastname: Polly