English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
Add to Basket
  Local TagsRelease HistoryDetailsSummary

Released
Journal Article

Connecting structure, dynamics and viscosity in sheared soft colloidal liquids: a medley of anisotropic fluctuations

MPS-Authors
/persons/resource/persons188182

Westermeier,  Fabian
Center for Free-Electron Laser Science, Notkestraße 85, 22607 Hamburg, Germany;
Miller Group, Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, Max Planck Society;

External Resource

http://dx.doi.org/10.1039/C5SM01707F
(Publisher version)

Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Westermeier, F., Pennicard, D., Hirsemann, H., Wagner, U. H., Rau, C., Graafsma, H., et al. (2016). Connecting structure, dynamics and viscosity in sheared soft colloidal liquids: a medley of anisotropic fluctuations. Soft Matter, 12(1), 171-180. doi:10.1039/C5SM01707F.


Cite as: https://hdl.handle.net/11858/00-001M-0000-0029-5385-B
Abstract
Structural distortion and relaxation are central to any liquid flow. Their full understanding requires simultaneous probing of the mechanical as well as structural and dynamical response. We provide the first full dynamical measurement of the transient structure using combined coherent X-ray scattering and rheology on electrostatically interacting colloidal fluids. We find a stress overshoot during the start-up of shear which is due to the strong anisotropic overstretching and compression of nearest-neighbor distances. The rheological response is reflected in uncorrelated entropy-driven intensity fluctuations. While the structural distortion under steady shear is well described by Smoluchowski theory, we find an increase of the particle dynamics beyond the trivial contribution of flow. After the cessation of shear, the full fluid microstructure and dynamics are restored, both on the structural relaxation timescale. We thus find unique structure-dynamics relations in liquid flow, responsible for the macroscopic rheological behavior of the system.