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arXiv · 1312.4142

Interacting hard rods on a lattice: Distribution of microstates and density functionals

Benaoumeur Bakhti·Gerhard Müller·Philipp Maass
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Abstract

We derive exact density functionals for systems of hard rods with first-neighbor interactions of arbitrary shape but limited range on a one-dimensional lattice. The size of all rods is the same integer unit of the lattice constant. The derivation, constructed from conditional probabilities in a Markov chain approach, yields the exact joint probability distribution for the positions of the rods as a functional of their density profile. For contact interaction ("sticky core model") between rods we give a lattice fundamental measure form of the density functional and present explicit results for contact correlators, entropy, free energy, and chemical potential. Our treatment includes inhomogeneous couplings and external potentials.

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Benaoumeur Bakhti, Gerhard Müller, Philipp Maass. 2013-12-15. Interacting hard rods on a lattice: Distribution of microstates and density functionals. https://doi.org/10.1063/1.4816379

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