Nematic-isotropic transition in a lattice model with quenched disordered impurities: A Monte Carlo study

摘要

We have performed Monte Carlo (MC) simulations of the lattice model for a fluid of elongated particles, mimicking liquid crystalline behavior and of this model in the presence of disordered quenched impurities. The interparticle interaction is chosen similar to the angular dependent term of the Berne-Pechukas potential. A pronounced first-order nematic-isotropic transition has been obtained for a bulk pure model at the Value for the elongation parameter, a=3. However, at a 5% concentration of disordered quenched impurities, we have observed a Very weak first-order transition in the simulations of the model at different sizes of the simulation volume. We have discussed a shift of the transition temperature, a suppression of the latent heat and the maxima of the heat capacity and susceptibility due to the presence of impurities. A histogram analysis and a finite-size scaling has been applied to the MC data. A comparison of the simulation data with the experimental results for liquid crystals confined to silica aerogels and porous glasses also has been performed. [References: 32]