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arXiv · 1207.0659

Statistical thermodynamics of long straight rigid rods on triangular lattices: nematic order and adsorption thermodynamic functions

D. A. Matoz-Fernandez·D. H. Linares·A. J. Ramirez-Pastor
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Abstract

The statistical thermodynamics of straight rigid rods of length $k$ on triangular lattices was developed on a generalization in the spirit of the lattice-gas model and the classical Guggenheim-DiMarzio approximation. In this scheme, the Helmholtz free energy and its derivatives were written in terms of the order parameter $δ$, which characterizes the nematic phase occurring in the system at intermediate densities. Then, using the principle of minimum free energy with $δ$ as a parameter, the main adsorption properties were calculated. Comparisons with Monte Carlo simulations and experimental data were performed in order to evaluate the reaches and limitations of the theoretical model.

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D. A. Matoz-Fernandez, D. H. Linares, A. J. Ramirez-Pastor. 2012-07-03. Statistical thermodynamics of long straight rigid rods on triangular lattices: nematic order and adsorption thermodynamic functions. https://arxiv.org/abs/1207.0659

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