We show that one may view the self-part and the distinct-part of the van Hove dynamic correlation function
of a simple fluid as the one-body density distributions of a binary mixture that evolve in time according to
dynamical density functional theory. For a test case of soft-core Brownian particles the theory yields results for
the van Hove function that agree quantitatively with those of our Brownian dynamics computer simulations. At
sufficiently high densities the free energy landscape underlying the dynamics exhibits a barrier as a function of
the mean particle displacement, shedding new light on the nature of glass formation. For hard spheres confined
between parallel planar walls the barrier height oscillates in phase with the local density, implying that the
mobility is maximal between layers, which should be experimentally observable in confined colloidal
dispersions.
Funding
A.J.A. and P.H. are grateful for
the support of EPSRC, and M.S. thanks the DFG for support
through the SFB TR6/D3.
History
School
Science
Department
Mathematical Sciences
Published in
PHYSICAL REVIEW E
Volume
75
Issue
4
Pages
? - ? (4)
Citation
ARCHER, A.J., HOPKINS, P. and SCHMIDT, M., 2007. Dynamics in inhomogeneous liquids and glasses via the test particle limit. Physical Review E, 75 (4), 040501.
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