Method for the measurement of the K[sub 22] nematic elastic constant

Raynes, E. P.; Brown, C. V.; Strömer, J. F.
January 2003
Applied Physics Letters;1/6/2003, Vol. 82 Issue 1, p13
Academic Journal
A technique has been developed for the measurement of the K[sub 22] twist elastic constant in nematic liquid crystal materials. This involves the measurement of the Freedericksz transition voltages in untwisted linear and π-twist regions in a wedge cell geometry. The method avoids the need for the accurate determination of the cell thickness and cholesteric pitch and is far more straightforward to implement than other methods in the literature. The validity of this method is demonstrated for the well-characterized material E7.


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