Anisotropic de Gennes Narrowing in Confined Fluids.

@article{Nygard2016AnisotropicDG,
  title={Anisotropic de Gennes Narrowing in Confined Fluids.},
  author={Kim Nyg̊ard and Johan Buitenhuis and Matias Kagias and Konstantins Jefimovs and Federico Zontone and Yuriy Chushkin},
  journal={Physical review letters},
  year={2016},
  volume={116 16},
  pages={
          167801
        }
}
The collective diffusion of dense fluids in spatial confinement is studied by combining high-energy (21 keV) x-ray photon correlation spectroscopy and small-angle x-ray scattering from colloid-filled microfluidic channels. We find the structural relaxation in confinement to be slower compared to the bulk. The collective dynamics is wave vector dependent, akin to the de Gennes narrowing typically observed in bulk fluids. However, in stark contrast to the bulk, the structure factor and de Gennes… 
View on PubMed
link.aps.org
27 Citations
Background Citations
3

Figures from this paper

27 Citations

Colloidal diffusion in confined geometries.

  • K. Nyg̊ard
  • Physics
    Physical chemistry chemical physics : PCCP
  • 2017
A common thread is to analyse colloidal diffusion in confined geometries in terms of the local density experienced by the colloidal particles, viz. at the level of anisotropic pair densities, which have recently become experimentally accessible.

Anisotropic Dynamics of Binary Particles in Confined Geometries.

Investigation reveals that particle size, particle-wall interaction, and slitpore width play different roles in affecting the oscillating behaviors along different directions, and yields the local mean square displacements in perpendicular and parallel directions, which agree remarkably well with prior experimental measurements.

Atomic Dynamics in Simple Liquid: de Gennes Narrowing Revisited.

It is found that the relaxation time increases monotonically with distance and the dependence on distance varies with dimension, which sheds new light on the interpretation of the de Gennes narrowing phenomenon and the α-relaxation time.

On De Gennes Narrowing of Fluids Confined at the Molecular Scale in Nanoporous Materials

Fluids in nanoporous materials are central in the energy/environmental crisis with key applications in adsorption, separation and catalysis. Yet, beyond well-documented confinement and surface…

Dynamical properties of densely packed confined hard-sphere fluids.

The numerical results reveal a nonmonotonic dependence of the power-law exponents on the slab width and a nontrivial kink in the low-frequency susceptibility spectra and qualitative agreement of these theoretical results to event-driven molecular dynamics simulations of polydisperse hard-sphere systems is found.

Tagged-particle dynamics in confined colloidal liquids.

It is shown that neither the microscopic dynamics nor the type of intermediate scattering function qualitatively changes the asymptotic dynamics in vicinity of the glass transition, and similar characteristics of confinement are found in the low-frequency susceptibility spectrum which are interpreted as footprints of parallel relaxation.

Tagged-particle motion in quasi-confined colloidal hard-sphere liquids

We investigate the tagged-particle motion in a strongly interacting quasi-confined liquid using periodic boundary conditions along the confining direction. Within a mode-coupling theory of the glass…

Static properties of quasi-confined hard-sphere fluids

Confined fluids display complex behavior due to layering and local packing. Here, we disentangle these effects by confining a hard-sphere fluid to the surface of a cylinder, such the circumference…

Dynamic properties of quasi-confined colloidal hard-sphere liquids near the glass transition

The complex behavior of confined fluids arising due to a competition between layering and local packing can be disentangled by considering quasi-confined liquids, where periodic boundary conditions…

Probing nonlinear velocity profiles of shear-thinning, nematic platelet dispersions in Couette flow using x-ray photon correlation spectroscopy

We report experiments employing x-ray photon correlation spectroscopy (XPCS) to characterize the velocity profiles of complex fluids in Couette flow. The approach involves modeling the XPCS…

21 References

I and J

Phys

  • Rev. Lett. 112, 158102
  • 2014

Phys

  • Rev. Lett. 100, 145901
  • 2008

Phys

  • Rev. E 62, 3909
  • 2000

Phys

  • Rev. Lett. 102, 068302 (2009). PRL 116, 167801
  • 2016

Phys

  • Rev. Lett. 99, 025702
  • 2007

Phys

  • Rev. Lett. 96, 138303
  • 2006

Phys

  • 139, 164701
  • 2013

we have carefully subtracted scattering data from the fluid film between the channel array and the glass cover

    Phys

    • Rev. Lett. 111, 235901
    • 2013