Nanosecond time scale dynamics of pseudo-nematic domains in the isotropic phase of liquid crystals
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چکیده
The slow reorientational dynamics of isotropic methoxybenzylidene-butylaniline (MBBA) were measured, using a transient grating optical Kerr effect experiment, over a wide temperature range (49.4 °-119.7 ° C). The range of validity of the Landau-de Gennes theory for hydrodynamic relaxation in ordered fluids is determined. The results are compared to previous experiments on pentylcyanobiphenyl (5CB). Both liquid crystals conform to the Landau-de Gennes theory until the pseudo-nematic domain correlation length falls below three molecular lengths.
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تاریخ انتشار 2002