Issue
EPL
Volume 82, Number 5, June 2008
Article Number 50007
Number of page(s) 5
Section General
DOI http://dx.doi.org/10.1209/0295-5075/82/50007
Published online 30 May 2008
EPL, 82 (2008) 50007
DOI: 10.1209/0295-5075/82/50007

Determination of the critical exponents for the isotropic-nematic phase transition in a system of long rods on two-dimensional lattices: Universality of the transition

D. A. Matoz-Fernandez, D. H. Linares and A. J. Ramirez-Pastor

Departamento de Física, Instituto de Física Aplicada, Universidad Nacional de San Luis-CONICET Chacabuco 917, 5700 San Luis, Argentina

antorami@unsl.edu.ar

received 14 March 2008; accepted in final form 17 April 2008; published June 2008
published online 30 May 2008

Abstract
Monte Carlo simulations and finite-size scaling analysis have been carried out to study the critical behavior and universality for the isotropic-nematic phase transition in a system of long straight rigid rods of length k (k-mers) on two-dimensional lattices. The nematic phase, characterized by a big domain of parallel k-mers, is separated from the isotropic state by a continuous transition occurring at a finite density. The determination of the critical exponents, along with the behavior of Binder cumulants, indicate that the transition belongs to the 2D Ising universality class for square lattices and to the three-state Potts universality class for triangular lattices.

PACS
05.50.+q - Lattice theory and statistics (Ising, Potts, etc.).
64.70.M- - Transitions in liquid crystals.
75.40.Mg - Numerical simulation studies.

© EPLA 2008