On the validity of Stokes-Einstein-Debye relations for rotational diffusion in colloidal suspensions
| Autor: | Albert P. Philipse, Gijsberta H. Koenderink, Haiyan Zhang, Gerhard Nägele, Dirk G. A. L. Aarts, M. Pavlik Lettinga |
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| Přispěvatelé: | Physics of Living Systems, Colloïden en grenslagen, Physical and Colloid Chemistry 1, Dep Scheikunde |
| Jazyk: | angličtina |
| Rok vydání: | 2003 |
| Předmět: |
Chemistry
Rotational diffusion Slip (materials science) Astrophysics::Cosmology and Extragalactic Astrophysics Molecular physics Condensed Matter::Soft Condensed Matter symbols.namesake Colloid Classical mechanics Dynamic light scattering ddc:540 symbols SPHERES Physical and Theoretical Chemistry Spectroscopy Scaling Astrophysics::Galaxy Astrophysics Debye |
| Zdroj: | Faraday Discussions, 123, 335-354. Royal Society of Chemistry Faraday discussions 123, 335-354 (2003). doi:10.1039/b204668g Koenderink, G H, Zhang, H, Aarts, D, Lettinga, M P, Philipse, A P & Nagele, G 2003, ' On the validity of Stokes-Einstein-Debye relations for rotational diffusion in colloidal suspensions ', Faraday Discussions, vol. 123, pp. 335-354 . https://doi.org/10.1039/b204668g Cambridge [u.a.] : Soc., Faraday discussions 123, 335-354 (2003). doi:10.1039/b204668g |
| ISSN: | 1359-6640 |
| DOI: | 10.1039/b204668g |
| Popis: | According to the Stokes-Einstein-Debye (SED) relation, the rotational diffusion coefficient of a colloidal tracer sphere scales with the inverse of the solvent viscosity. Here we investigate the generalization of the SED relation to tracer diffusion in suspensions of neutral and charged colloidal host spheres. Rotational diffusion coefficients are measured with dynamic light scattering and phosphorescence spectroscopy, and calculated including two- and three-particle hydrodynamic interactions. We find that rotational tracer diffusion is always faster than predicted by the SED relation, except for large tracer/host size ratios lambda. In the case of neutral particles this observation is rationalized by introducing an apparent lambda-dependent slip boundary coefficient. For charged spheres at low ionic strength, large deviations from SED scaling are found due to the strongly hindered host sphere dynamics. Finally, we present some first experiments on tracer sphere diffusion in suspensions of host rods, showing that hydrodynamic hindrance by rods is much stronger than by spheres. We conclude by pointing to some interesting unresolved issues for future research. ispartof: pages:335-354 ispartof: Faraday Discussions vol:123 issue:1 pages:335-354 ispartof: location:EDINBURGH: SCOTLAND status: published |
| Databáze: | OpenAIRE |
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