Topological point defects in liquid crystalline polymers

The full range of point defects of the type described by Poincaroné is defined in terms of the disclination loop which would transform them into a monodomain. Calculations of energy of the points as a function of the defining angle, α, give the relative contributions of the splay, twist and bend components. Defects observed on fracture surfaces of a quenched liquid crystalline polymer are consistent with the point geometry predicted to have minimum splay distortion, and thus accountable for in terms of the high splay elastic constant characteristic of the polymeric nematic state.