title: Surface energy of talc and chlorite: Comparison between electronegativity calculation and immersion results.
abstract: The surface energies of talc and chlorite is computed using a simple model, which uses the calculation of the electrostatic energy of the crystal. It is necessary to calculate the atomic charges. We have chosen to follow Henry's model of determination of partial charges using scales of electronegativity and hardness. The results are in correct agreement with a determination of the surface energy obtained from an analysis of the heat of immersion data. Both results indicate that the surface energy of talc is lower than the surface energy of chlorite, in agreement with observed behavior of wettability. The influence of Al and Fe on this phenomenon is discussed. Surface energy of this type of solids seems to depend more strongly on the geometry of the crystal than on the type of atoms pointing out of the surface; i.e., the surface energy depends more on the physics of the system than on its chemistry.
authors.affiliation: L A M M I, UMR 5072, CC 015, Université Montpellier 2, Sciences et Techniques, 34095 Montpellier Cedex 05, France. jmd@univ-montp2.fr
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Douillard
authors.forename: Fabrice
authors.initials: F
authors.lastname: Salles
authors.forename: Marc
authors.initials: M
authors.lastname: Henry
authors.forename: Harold
authors.initials: H
authors.lastname: Malandrini
authors.forename: Frédéric
authors.initials: F
authors.lastname: Clauss