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arXiv · 1808.03839

Biaxial layering transition of hard rod-like particles in narrow slit-like pores

Hamdollah Salehi·Sakine Mizani·Roohollah Aliabadi·Szabolcs Varga
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Abstract

The phase behavior of hard rectangular rods with length L and diameter D is studied in a narrow slit-like pore using the Parsons-Lee density functional theory. Using the restricted orientation approximation, we find strong adsorption at the walls with planar ordering, second order uniaxial-biaxial ordering transitions and first order layering transitions. The layering transition takes place between two fluids having n and n+1 layers, where the layer spacing is in the order of D. In the case of weak shape anisotropy (L/D=3), the coexisting fluids can be either uniaxial or biaxial, while both phases are found to be biaxial for L/D=6 and L/D=9. Interestingly, even two or more layering transitions can be observed with increasing density at a given shape anisotropy and pore width.

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Hamdollah Salehi, Sakine Mizani, Roohollah Aliabadi, Szabolcs Varga. 2018-08-11. Biaxial layering transition of hard rod-like particles in narrow slit-like pores. https://doi.org/10.1103/physreve.98.032703

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