Comments on the Relaxation Process in the Cholesteric-Nematic Transition

  • R. A. Kashnow
  • J. E. Bigelow
  • H. S. Cole
  • C. R. Stein


The relaxation process by which a field-aligned nematic state returns to a helicoidal structure has been the subject of several studies. In this paper, we report some new transient optical and capacitive measurements which emphasize the dependence of the relaxation on sample boundary conditions. Homeotropic samples exhibit a delay time after field removal, followed by nucleation of the decay sequence about isolated points. During the decay, the capacitance decreases monotonically, but the light-scattering transient is structured even in the absence of polarizing optics. A spiral domain structure is observed for these samples. For samples with parallel boundary conditions, the transient capacitance data exhibit a minimum which supports earlier inferences of a tilted-Grandjean-planar structure.


Relaxation Process Effective Dielectric Constant Director Distribution Capacitive Measurement Domain Texture 
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Copyright information

© Plenum Press, New York 1974

Authors and Affiliations

  • R. A. Kashnow
    • 1
  • J. E. Bigelow
    • 1
  • H. S. Cole
    • 1
  • C. R. Stein
    • 1
  1. 1.General Electric Corporate Research and DevelopmentUSA

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