title: Light-scattering form factors of asymmetric particle dimers from heteroaggregation experiments.
abstract: Measurements of form factors of asymmetric particle dimers composed of oppositely charged polystyrene latex particles are presented. These measurements are based on time-resolved static and dynamic light scattering on dilute aggregating aqueous suspensions. The experimental form factors are compared with independent calculations based on the superposition T-matrix method and Rayleigh-Debye-Gans (RDG) approximation. While the RDG approximation is found to be reliable only up to particle diameters of about 250 nm, the superposition T-matrix method is very accurate for all types of dimers investigated. The present results show clearly the appropriateness of the superposition T-matrix method to estimate the optical properties of colloidal particles in the micrometer range reliably.
authors.affiliation: Department of Inorganic, Analytical, and Applied Chemistry, University of Geneva, 1211 Geneva 4, Switzerland.
authors.forename: Paolo
authors.initials: P
authors.lastname: Galletto
authors.forename: Wei
authors.initials: W
authors.lastname: Lin
authors.forename: Michael I
authors.initials: MI
authors.lastname: Mishchenko
authors.forename: Michal
authors.initials: M
authors.lastname: Borkovec