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Wang-Landau Monte Carlo simulation of isotropic-nematic transition in liquid crystals

D. Jayasri·V. S. S. Sastry·K. P. N. Murthy
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Abstract

Wang and Landau proposed recently, a simple and flexible non-Boltzmann Monte Carlo method for estimating the density of states, from which the macroscopic properties of a closed system can be calculated. They demonstrated their algorithm by cocontinuous energy spectrum. We propose in this paper modifications nsidering systems with discrete energy spectrum. We find that the Wang-Landau algorithm does not perform well when the system has continuous energy spectrum. We propose in this paper modifications to the algorithm and demonstrate their performance on a lattice model of liquid crystalline system (with Lebwohl-Lasher interaction having continuously varying energy), exhibiting transition from high temperature isotropic to low temperature nematic phase.

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D. Jayasri, V. S. S. Sastry, K. P. N. Murthy. 2005-05-11. Wang-Landau Monte Carlo simulation of isotropic-nematic transition in liquid crystals. https://doi.org/10.1103/physreve.72.036702

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