Multiple Rayleigh-Gans-Debye Light Scattering in Colloidal Systems

Abstract

To study interaction between Brownian particles, experiments on highly concentrated dispersions must be performed.Using light-scattering techniques the experimental data are difficult to interpret due to multiple scattering effects.Not only photons scattered once, but also photons scattered more than once are detected. To obtain information about interaction between particles and their internal structure, one needs the first-order scattered intensity due to photons scattered only once. Therefore scattering data should be corrected for these so called higher-order scattered intensities. In this paper general expressions for the n^th-order scattered electric field strengths are derived. From these equations, by ensemble averaging, equations for the total average scattered intensity, and the total intensity auto-correlation function are derived, assuming that only single and double scattering events are important. Using these equations, iterative correction procedures are proposed.