The investigation of relaxation processes in chosen liquid crystals by ultrasonic and dielectric methods
Abstract
Relaxation processes have been found to occur in 4-n-methoxybenzoated-4-n-pentylphenylene and 4-n-octyloxyphenylene-4-m-pentyloxybenzoate. The findings are based on ultrasonic and dielectric investigations. Both chemical compounds exhibit two regions of relaxation in the range of frequencies investigated. A comparison has Men made of the values of the activation energy derived from the dielectric and acoustic investigations.References
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[3] J. F. DYRO, P. D. EDMONDS, Ultrasonic absorption and dispersion at phase transition in liquid crystalline systems: N-octylamine – water, Molecular Crystals and Liquid Crystals, 8, 141-155 (1996).
[2] A. DRZYMAŁA, M. CIEŚLAK, K. KRUPA, A. SZYMAŃSKI, On the mechanical relaxation in ultrafrequency range in 4-n-methoxybenzoesane-4-n-pentylphenylene, IIT Liquid Crystal Conference, Budapest 1979.
[3] J. F. DYRO, P. D. EDMONDS, Ultrasonic absorption and dispersion at phase transition in liquid crystalline systems: N-octylamine – water, Molecular Crystals and Liquid Crystals, 8, 141-155 (1996).
