Gravitational compression in colloidal suspension
- 1 December 1985
- journal article
- Published by IOP Publishing in Journal of Physics A: General Physics
- Vol. 18 (17), 3389-3398
- https://doi.org/10.1088/0305-4470/18/17/021
Abstract
Gravitational effect in colloidal suspensions is examined both theoretically and experimentally by light scattering. In contrast to the previous theory the present theory predicts the cube of the nearest-neighbour distance to vary linearly as a function of height of the suspension. The position of the first peak in the static structure factor of the suspension having liquid-like order is used to obtain average nearest-neighbour distance. The experimental data fit well to the present theory. The bulk modulus of the liquid order estimated for the first time by this method is found to evolve as a function of time. The time taken for the colloidal suspension to reach gravitational equilibrium as well as deionisation equilibrium is obtained. The time to reach gravitational equilibrium is found to be much less than earlier theoretical estimates based on a simple model. A possible mechanism for this is proposed. Concentration dependence of the saturation bulk modulus is obtained and discussed.Keywords
This publication has 12 references indexed in Scilit:
- A new set-up for measuring angle-resolved polarised light scatteringJournal of Physics E: Scientific Instruments, 1984
- Direct determination of free energies of colloidal dispersionsPhysics Letters A, 1983
- Multiple Rayleigh-Gans-Debye scattering in colloidal systems-general theory and static light scatteringPhysica A: Statistical Mechanics and its Applications, 1983
- Colloidal crystalsContemporary Physics, 1983
- Generalized hydrodynamics of systems of Brownian particlesAdvances in Physics, 1983
- Dynamics of colloidal crystals and colloidal liquidsJournal of Physics A: General Physics, 1982
- Elastic properties of colloidal crystals and glassesThe Journal of Chemical Physics, 1982
- Single colloidal crystalsNature, 1979
- Gravitational Compression of Crystallized Suspensions of Polystyrene SpheresScience, 1977
- Light scattering study of dynamic and time-averaged correlations in dispersions of charged particlesJournal of Physics A: General Physics, 1975