title: Specific ion adsorption and short-range interactions at the air aqueous solution interface.
abstract: We have investigated the surface composition of alkali-halide aqueous solutions using grazing incidence x-ray fluorescence. Using mixtures of salts as a means to enhance the short-range effects, small differences in concentration over a few angstrom could be resolved, with, for example I- or Br- > Cl-. In order to explain our data, we need to include an effective potential accounting for the short-range (A) solvent mediated couplings, responsible for specific effects together with dispersion forces. This attractive potential (few k{B}T for halides) leads to concentration profiles which are in good agreement with recent numerical simulations.
authors.affiliation: Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire, SCM, bât 125, CEA Saclay, F-91191, Gif-sur-Yvette Cedex, France.
authors.forename: Viswanath
authors.initials: V
authors.lastname: Padmanabhan
authors.forename: Jean
authors.initials: J
authors.lastname: Daillant
authors.forename: Luc
authors.initials: L
authors.lastname: Belloni
authors.forename: Serge
authors.initials: S
authors.lastname: Mora
authors.forename: Michel
authors.initials: M
authors.lastname: Alba
authors.forename: Oleg
authors.initials: O
authors.lastname: Konovalov
mesh_terms: D000327:Adsorption; D012492:Salts; D012996:Solutions; D014867:Water; D014965:X-Rays
chemical_list: D012492:Salts; D012996:Solutions; D014867:Water