title: Interfacial water on Cl- and H-terminated Si(111) surfaces from first-principles calculations.
abstract: The properties of interfacial water on Cl- and H-terminated Si(111) surfaces are investigated using a first-principles approach and characterized by means of energetic analysis combined with hydrogen-bond counting. The interaction of water with both substrates is found to be significantly weak, although bonding with the Cl-terminated Si(111) surface is relatively stronger because of the electrostatic contribution. According to a molecular picture for attributing the hydrophilic/hydrophobic character, both surfaces should be considered hydrophobic, at variance with the interpretation of recent ultrafast electron crystallography experiments, which seems instead to support a hydrophilic nature of the Cl-terminated Si(111) substrate.
authors.affiliation: Dipartimento di Fisica G. Galilei, Università di Padova, via Marzolo 8, I-35131 Padova, Italy.
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Silvestrelli
authors.forename: Flavio
authors.initials: F
authors.lastname: Toigo
authors.forename: Francesco
authors.initials: F
authors.lastname: Ancilotto