Monte Carlo lattice simulations of the elastic behaviour of nematic liquidcrystals

A pairwise additive potential, which approximately reproduces the free ener gy density for the elastic deformations of a nematic liquid crystal, origin ally proposed by Gruhn and Hess, has been investigated by simulating the th ree Freedericksz transitions as well as that of the Schadt-Helfrich cell. T he pair potential depends on the three elastic constants K-1, K-2 and K-3 f or the splay, twist acid bend deformations, respectively. The results of th e simulations are compared with the analytical solutions obtained from cont inuum theory in order to test the accuracy of the model potential at a quan titative level. This comparison is also made for different temperatures to explore the influence of director fluctuations on the elastic behaviour.