Electric Field Effects on the Elastic Constants of Nematics. I

Abstract

The free energy density expression for nematics in an external electric field is derived both from a quasi-molecular approach similar to that used by Nehring and Saupe and a macroscopic approach based entirely on the symmetry properties of nematics. Under the special model assumed in the quasi-molecular theory the expressions of the elastic constants obtained from the two different methods agree with each other when one makes a proper choice of the material parameters introduced in the macroscopic theory.