Recently, current vs voltage measurements have revealed a nonstandard behavior of the electric conductivity within some nematic liquid crystals (NLC) samples, and the results have been associated with the local orientational order at the free surfaces of the liquid crystal. We have used Monte Carlo simulation of a liquid crystal in a cell with two free surfaces at the opposite sides to understand how a local director imposed by free surfaces competes with the homeotropic alignment imposed by electrodes of the nematic cell.

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We report Monte Carlo simulations based on the Lebwohl-Lasher model for characterizing the molecular director configuration in a nematic liquid crystal cell presenting periodical boundary anchoring conditions. We demonstrate the molecular orientation and spatial behaviour, while profiling the local order parameter distribution for the proposed confining geometry, as well as the boundary and interface interaction fields propagation through the namatic bulk for various temperatures in the proximity of the nematic-isotropic transition. Simulations were also performed concerning with the light passing through the planar and homeotropic periodical regions of the nematic cell and a mapping of the transmitted intensity was obtained for several ambient temperatures. The boundary constraints and the selected periodical geometry of the simulated system play an extremely important role for the demonstrated optical and orientational properties of the liquid crystalline material.

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