Abstract
Nuclear Magnetic Resonance proton spin-lattice measurements in phentylcyano-phenylcy-clohexane liquid crystal at the Larmor frequencies 1.235 MHz and 48 kHz in a temperature range above the nematic-isotropic phase transition are reported.
The Landau-De Gennes theory for nematic-isotropic phase transition is used to analize the temperature dependence of the spin-lattice correlation functions. We conclude that the low frequency approximation can be applied only when the experiment is carried out at Larmor frequencies in the kHz range.
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