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arXiv · 2110.14722

Nonergodicity parameters of confined hard-sphere glasses

Suvendu Mandal·Simon Lang·Vitalie Boţan·Thomas Franosch
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Abstract

Within a recently developed mode-coupling theory for fluids confined to a slit we elaborate numerical results for the long-time limits of suitably generalized intermediate scattering functions. The theory requires as input the density profile perpendicular to the plates, which we obtain from density functional theory within the fundamental-measure framework, as well as symmetry-adapted static structure factors which can be calculated relying on the inhomogeneous Percus-Yevick closure. Our calculations for the nonergodicity parameters for both the collective as well as for the self motion are in qualitative agreement with our extensive event-driven molecular dynamics simulations for the intermediate scattering functions for slightly polydisperse hard-sphere systems at high packing fraction. We show that the variation of the nonergodicity parameters as a function of the wavenumber correlates with the in-plane static structure factors, while subtle effects become apparent in the structure factors and relaxation times of higher mode-indices. A criterion to predict the multiple reentrant from the variation of the in-plane static structure is presented.

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Suvendu Mandal, Simon Lang, Vitalie Boţan, Thomas Franosch. 2021-10-27. Nonergodicity parameters of confined hard-sphere glasses. https://doi.org/10.1039/c7sm00905d

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