Molecular dynamics in liquid crystals by dielectric relaxation and neutron scattering
- 1 June 1988
- journal article
- research article
- Published by Taylor & Francis in Liquid Crystals
- Vol. 3 (6-7) , 893-900
- https://doi.org/10.1080/02678298808086546
Abstract
Detailed dielectric permittivity and relaxation investigations have been performed on compounds having different liquid-crystalline phases. At the smectic B–smectic A as well as the smectic G–smectic B transitions definite jumps were found in the dielectric relaxation times associated with rotation of the molecules around their short axis. For the interpretation of the large jumps in the relaxation times the change of the phonon spectra at the two dimensional crystal-two dimensional liquid phase transition was assumed. To verify this idea an inelastic neutron scattering study was performed. The measurements have proved the good orientation of the smectic A and smectic B phases. The values of the layer spacing, and the appearance of libron peaks for the smectic B phase at different momentum transfer were determined.Keywords
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