Distortional Lifshitz Vectors and Helicity in Nematic Free Energy Density

Author(s): Amelia Carolina Sparavigna

Here we discuss the free energy of nematic liquid crystals using two vectors and the helicity, with the aim of having a compact form of its density. The two vectors are due to the splay and bend distortions of the director field. They have a polar nature, whereas the helicity is a pseudoscalar.

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