title: Noncentral forces in crystals of charged colloids.
abstract: The elastic properties of fcc crystals consisting of charge stabilized colloidal particles are determined from real space imaging experiments using confocal microscopy. The normal modes and the force constants of the crystal are obtained from the fluctuations of the particles around their lattice sites using the equipartition theorem. We show that the Cauchy relation is not fulfilled and that only noncentral many-body forces can account for the elastic properties.
authors.affiliation: Physics Department, University of Konstanz, 78457 Konstanz, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Reinke
authors.forename: H
authors.initials: H
authors.lastname: Stark
authors.forename: H-H
authors.initials: HH
authors.lastname: von Grünberg
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Schofield
authors.forename: G
authors.initials: G
authors.lastname: Maret
authors.forename: U
authors.initials: U
authors.lastname: Gasser
mesh_terms: D003102:Colloids / Q000737:chemistry*; D003460:Crystallization; D004548:Elasticity; D008956:Models, Chemical; D019904:Polymethyl Methacrylate / Q000737:chemistry
chemical_list: D003102:Colloids; D019904:Polymethyl Methacrylate