Calculation of flexoelectric coefficients for a nematic liquid crystal by atomistic simulation

Equilibrium molecular dynamics calculations have been performed for the liquid crystal molecule n-4-(trans-4-n-pentylcyclohexyl)benzonitrile (PCH5) using a fully atomistic model. Simulation data have been obtained for a series of temperatures in the nematic phase. The simulation data have been used to calculate the flexoelectric coefficients e(s) and e(b) using the linear response formalism of Osipov and Nemtsov [M. A. Osipov and V. B. Nemtsov, Sov. Phys. Crstallogr. 31, 125 (1986)]. The temperature and order parameter dependence of e(s) and e(b) are examined, as are separate contributions from different intermolecular interactions. Values of e(s) and e(b) calculated from simulation are consistent with those found from experiment.