title: Position-displacement correlations in QELSS spectra of non-dilute colloids.
abstract: This paper examines relationships between the quasielastic light scattering spectrum S(q, t) and the distribution functions for particle displacements over various times. For dilute probes in a complex, non-scattering fluid, S(q, t) is determined by the even moments <X(t)(2n)> of the one-particle displacement distribution function P(X, t). For concentrated scattering particles, S(q, t) is not determined by P(X, t). Instead, S(q, t) is determined in part by P(X, t) and in part by a spatial Fourier transform of the two particle displacement distribution function P(2)(X, t, R(12)). Here, X is the displacement of particle 1 during t, and R(12) is the component (at t = 0), parallel to the scattering vector q, of the vector from particle 1 to a second particle 2.
authors.affiliation: Department of Physics, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA. phillies@wpi.edu
authors.forename: George D J
authors.initials: GD
authors.lastname: Phillies
mesh_terms: D003102:Colloids / Q000737:chemistry*; D008027:Light; D012542:Scattering, Radiation; D013057:Spectrum Analysis
chemical_list: D003102:Colloids