Study of elastic constant ratios in nematic liquid crystals -: art. no. 051915

A technique has recently been proposed for determining the elastic constant ratio K-22/K-11 in nematic liquid crystals [E. P. Raynes, C. V. Brown, and J. F. Stromer, Appl. Phys. Lett. 82, 13 (2003)]. This technique has been applied to five nematic materials that cover a range of K-33/K-11 elastic constant ratio values. An unusually high value of K-22/K-11 is found in one material. High values of the ratio K-22/K-11 tended to occur in materials that also have high values of the ratio K-33/K-11. The results are validated with independent measurements of K-22 from cholesteric helix unwinding. (c) 2006 American Institute of Physics.