Cholesterics continuum theory

The fact that the properties of the cholesteric liquid crystal are not invariant with respect to reflexion introduces some additional complexity into the equations of the continuum theory. The possibility now exists of... 

Leslie, F.M. Continuum theory of cholesteric liquid crystals. Mol. Cryst. Liq. Cryst. 7, 407 20 (1969)... 

C. W. Oseen, Arkiv Mat. Astron. Fysik 1928, 21A,l. This paper, like the earlier papers on the continuum theory, is written in German, a language that Oseen stoped using from 1933. References to Oseen s work are nowadays almost uniquely given to his article in English in Trans. Faraday Soc. 1933, 29, 883. While it is true that Eq. (1) is stated there, the article essentially contains the first comprehensive theory of the optical properties of cholesteric liquid crystals. 

Eqs. [5] and [6] are the fundamental equations of the elastic continuum theory of nematic and cholesteric liquid crystals (for nematics Xo in Eq. [5] is set equal to ). In the following section we use the fundamental equations to solve four examples as illustrations for their applications. 

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