Strongly confined fluids: Diverging time scales and slowing down of equilibration

Abstract

The Newtonian dynamics of strongly confined fluids exhibits a rich behavior. Its confined and unconfined degrees of freedom decouple for confinement length $L\to 0$. In that case and for a slit geometry the intermediate scattering functions $S_{\mu \nu }(q,t)$ simplify, resulting for $(\mu ,\nu )\ne (0,0)$ in a Knudsen-gas like behavior of the confined degrees of freedom, and otherwise in $S_{\parallel }(q,t)$, describing the structural relaxation of the unconfined ones. Taking the coupling into account we prove that the energy fluctuations relax exponentially. For smooth potentials the relaxation times diverge as $L^{-3}$ and $L^{-4}$, respectively, for the confined and unconfined degrees of freedom. The strength of the $L^{-3}$ divergence can be calculated analytically. It depends on the pair potential and the two-dimensional pair distribution function. Experimental setups are suggested to test these predictions.

no figures

References in corpus (9)

• Rigorous Inequalities between Length and Time Scales in Glassy Systems
• Layering and position-dependent diffusive dynamics of confined fluids
• Glass Transition in Confined Geometry
• Multiple reentrant glass transitions in confined hard-sphere glasses
• Mode-coupling theory of the glass transition for confined fluids
• Fluids in Extreme Confinement
• Structural quantities of quasi-two-dimensional fluids
• Glassy dynamics in confinement: Planar and bulk limit of the mode-coupling theory
• The way from microscopic many-particle theory to macroscopic hydrodynamics

Cited by in corpus (4)

• Diverging time scale in the dimensional crossover for liquids in strong confinement
• Mode-coupling theory of the glass transition for colloidal liquids in slit geometry
• Structural properties of liquids in extreme confinement
• Dynamic properties of quasi-confined colloidal hard-sphere liquids near the glass transition