title: Ice tessellation on a hydroxylated silica surface.
abstract: The adsorption of water on a fully hydroxylated silica surface is studied by using density-functional total-energy and molecular dynamics calculations. The (100) surface of beta(alpha)-cristobalite covered by geminal hydroxyls has been taken as the substrate. A well-ordered and stable two-dimensional ice with quadrangular and octagonal patterns of hydrogen bond (H-bond) networks-an ice tessellation-is found on the surface for the first time. With the vibrational recognition, the four water molecules in the quadrangle are found to be bonded by strong H bonds while the quadrangles are connected to each other by weak H bonds. This configuration is the most stable, because all the water molecules are fully saturated with H bonds either to each other or to the surface hydroxyl groups.
authors.affiliation: State Key Laboratory for Surface Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Yang
authors.forename: Sheng
authors.initials: S
authors.lastname: Meng
authors.forename: L F
authors.initials: LF
authors.lastname: Xu
authors.forename: E G
authors.initials: EG
authors.lastname: Wang