Photon Correlation Measurements of Colloidal Size Distributions. II. Details of Histogram Approach and Comparison of Methods of Data Analysis

Abstract

Experimental evaluation of particle size distributions using photon correlation spectroscopy according to the methods of cumulants and of Pearson, the Laplace transform, and the histogram approach is presented. Simulated data and Dow latex spheres measured at different scattering angles show that although the Laplace transform method can occasionally distinguish discrete exponential decay times and the Pearson method is applicable for unimodal distributions, the histogram technique provides a general approach to the polydispersity problem. Furthermore, it can be used for systems exhibiting bimodal distributions where the method of cumulants must be treated with care and the Pearson method fails.