An electromechanical liquid crystal model of vesicles

An electromechanical liquid crystal model is developed for characterizing the equilibrium morphology of a lipid vesicle under coupled mechanical and electrical fields. A general equation that governs the vesicle shape is established, which incorporates the effects of elastic bending, osmotic pressure, surface tension, Maxwell pressure, as well as flexoelectric and dielectric properties of the lipid membrane. As an illustration of the model, the problem of an axisymmetric vesicle (e.g., a sphere or a cylinder) in a uniform electric field is considered in some detail, with results in agreement with relevant experimental results. The model provides an efficient tool for studying morphological evolution of dielectric vesicles under mechanical and electrical fields.