Reorientation under dielectric interaction

The dielectric constants e// and ej are related to the permittivities by e// = 1 +xn cj. = 1 +Xl-Therefore b x =Xu Xl = // - j. = The electric energy of the liquid crystal per unit volume is approximately given by (detailed discussion will be presented in Chapter 7) 

When the applied field is low, Ae can be approximately considered as a constant, independent of the field. The first term on the right side of Equation (4.2) is independent of the orientation of the director with respect to the applied field, and thus can be neglected in considering the reorientation of liquid crystals in electric fields. The second term depends on the orientation of the 

---