Adsorption and diffusion of H2O molecule on the Be(0001) surface: A density-functional theory study

摘要

Using first-principles calculations, we systematically study the adsorptionbehavior of a single molecular H$_{2}$O on the Be(0001) surface. We find thatthe favored molecular adsorption site is the top site with an adsorption energyof about 0.3 eV, together with the detailed electronic structure analysis,suggesting a weak binding strength of the H$_{2}$O/Be(0001) surface. Theadsorption interaction is mainly contributed by the overlapping between the $s$and $p_{z}$ states of the top-layer Be atom and the molecular orbitals 1$b_{1}$and 3$a_{1}$ of H$_{2}$O. The activation energy for H$_{2}$O diffusion on thesurface is about 0.3 eV. Meanwhile, our study indicates that no dissociationstate exists for the H$_{2}$O/Be(0001) surface.