0000000000427082
AUTHOR
J. Kanetakis
Rotational diffusion of colloid spheres in concentrated suspensions studied by deuteron NMR
We present a study of the application of deuteron-nuclear magnetic resonance spectroscopy (NMR) to the investigation of the rotational diffusion of spherical colloidal particles. We performed NMR pulse experiments on colloidal suspensions of polystyrene latex spheres in water-glycerol mixtures in a wide range of particle volume fractions \ensuremath{\varphi} from the dilute suspension up to \ensuremath{\varphi}=0.504. We have analyzed the stimulated echo NMR signal in the time domain. The full shape of the orientational correlation function deviates from an exponential behavior in the whole \ensuremath{\varphi} range examined. We evaluate the rotational diffusion coefficient and calculate i…
Simultaneous measurement of rotational and translational diffusion by forced Rayleigh scattering. Colloid spheres in suspension
Abstract It is shown that the technique of forced Rayleigh scattering, traditionallyemployed to probe translational diffusion, can be employed to probe rotational diffusion as well. Thus with a single experiment both quantities are measured. The system under investigation is colloid spheres suspended in a glass-forming liquid. Furthermore, it is shown that the Stokes-Einstein and Debye-Stokes-Einstein relations for translational and rotational diffusion, respectively, are valid for spherical colloid particles in a supercooled liquid matrix in the vicinity of the glassy state.