A Molecular Theory of the Nematic to Nematic Phase Transition in Strongly Polar Compounds
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چکیده
As described in the previous chapter, the nematic (N) liquid crystal is characterised by a long range orientational order of the long axes of the molecules without a long range positional order of their centres of mass (see section 1.2.1, chapter-1). The preferred axis of orientation in the nematic liquid crystal, called the director, is represented by the unit vector n ^ . The extent of orientational order in a cylindrically symmetric nematic liquid crystal is given by the so-called scalar order parameter S defined as
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