Numerical Simulation Of A Voltage-Dependent Surface-Induced Molecular Reorientation In A Confined Nematic Liquid Crystal

摘要

We present a computer simulation of the voltage-dependent orientational ordering of a nematic liquid crystal within the lattice approximation, confined between two substrates with different anchoring for each surface. The system is studied by analyzing the response of the molecular reorientation near the surfaces as a function of the applied voltage. The model considers a molecular interaction responsible for the nematic phase that includes a superposition of the anisotropic induced-dipole-induced-dipole and isotropic Maier-Saupe interactions, whereas for the nematic-surface intermolecular interaction we assume the Rapini-Papoular form. The response to the external electric field is studied by calculating the dielectric constant tensor, based on a model through the molecular polarizability. We particularly discussed the case for negative dielectric anisotropy that could have relevance for the voltage controlled twist effect. The simulation is carried through a numerical relaxation method for the total energy of the system.