Spin Relaxation and Self-Diffusion in Liquid Crystals

Abstract

The frequency and temperature dependence of proton relaxation times have been measured for the nematic liquid-crystal and isotropic liquid phases of $p$-azoxyanisole and $p$-azoxyphenetole as well as for the "neat" mesophase of sodium stearate. Self-diffusion coefficients were determined by the proton-spin-echo method. The anomalous effects found are interpreted in terms of collective long-range-order fluctuations in the nematic region and a residual order in the isotropic liquid.