A new formula for the data analysis in the quasielastic light scattering with the sinusoidal electric field (QELS-SEF) was derived from the time-averaged autocorrelation function. This time-average process exactly corresponds to the actual experimental procedure which is performed with a correlator used in the QELS-SEF measurement. The new formula was applied to the power spectrum of the polystyrene latex solution in the heterodyne mode of QELS-SEF, and then was found to fit quite well to the experimental data. By this fitting procedure, we revealed the dependences of the electrophoretic mobility μ and the apparent diffusion constant Dapp of the polystyrene latex on the frequency and amplitude of the applied ac electric field. Thus, the frequency dispersion or relaxation of Dapp was observed in the same frequency region as the dielectric relaxation.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry