Inhomogeneous diffusion in confined colloidal suspensions.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40297974.
- Also identified by DOI 10.1039/d5sm00120j and PMC identifier 12038795.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We have performed confocal microscopy experiments and computer simulations of colloidal suspensions with moderate volume fraction confined between two quasi-parallel, rough walls [A. Villada-Balbuena <i>et al.</i>, Soft Matter, 2022, <b>18</b>, 4699-4714]. Here we investigate many facets of the dynamical properties of the system, such as confined and inhomogeneous diffusion, mean first-passage times and generalized incoherent scattering functions. We observe that the experiment features strong footprints of the confinement in the dynamical properties, such as inhomogeneous diffusion coefficients and non-zero off-diagonal elements in the incoherent scattering function which we can quantitatively model and analyze with computer simulations. This allows us, for example, to systematically investigate the impact of surface roughness. Our comparative study therefore advances the fundamental understanding of the impact of confinement on dynamics in fluids and colloidal suspensions.