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arXiv · 0712.4361

Entropy-driven phase transition in a system of long rods on a square lattice

D. H. Linares·F. Roma·A. J. Ramirez-Pastor
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Abstract

The isotropic-nematic (I-N) phase transition in a system of long straight rigid rods of length k on square lattices is studied by combining Monte Carlo simulations and theoretical analysis. The process is analyzed by comparing the configurational entropy of the system with the corresponding to a fully aligned system, whose calculation reduces to the 1D case. The results obtained (1) allow to estimate the minimum value of k which leads to the formation of a nematic phase and provide an interesting interpretation of this critical value; (2) provide numerical evidence on the existence of a second phase transition (from a nematic to a non-nematic state) occurring at density close to 1 and (3) allow to test the predictions of the main theoretical models developed to treat the polymers adsorption problem.

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D. H. Linares, F. Roma, A. J. Ramirez-Pastor. 2008-03-10. Entropy-driven phase transition in a system of long rods on a square lattice. https://doi.org/10.1088/1742-5468%2F2008%2F03%2Fp03013

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