title: Metal work-function changes induced by organic adsorbates: a combined experimental and theoretical study.
abstract: The role of molecular dipole moment, charge transfer, and Pauli repulsion in determining the work-function change (Deltaphi) at organic-metal interfaces has been elucidated by a combined experimental and theoretical study of (CH(3)S)(2)/Au(111) and CH(3)S/Au(111). Comparison between experiment and theory allows us to determine the origin of the interface dipole layer for both phases. For CH(3)S/Au(111), Deltaphi can be ascribed almost entirely to the dipole moment of the CH(3)S layer. For (CH(3)S)(2)/Au(111), a Pauli repulsion mechanism occurs. The implications of these results on the interpretation of Deltaphi in the presence of strongly and weakly adsorbed molecules is discussed.
authors.affiliation: INFM Center for nanoStructures and bioSystem at Surfaces and Dipartimento di Fisica, Università di Modena e Reggio Emilia, Modena, Italy. vderenzi@unimore.it
authors.forename: V
authors.initials: V
authors.lastname: De Renzi
authors.forename: R
authors.initials: R
authors.lastname: Rousseau
authors.forename: D
authors.initials: D
authors.lastname: Marchetto
authors.forename: R
authors.initials: R
authors.lastname: Biagi
authors.forename: S
authors.initials: S
authors.lastname: Scandolo
authors.forename: U
authors.initials: U
authors.lastname: Del Pennino