Submicrometer-size droplets of monomeric liquid crystals dispersed in a solid polymer matrix are studied by deuterium NMR. Phase-separation processes are used to achieve droplets of a size comparable and less than the magnetic coherence length {ξ}{~}0.5 {μ}m, of the NMR magnetic field, 4.7 T. Selectively deuterated (4'-pentoxy- and 4'-methoxy-) 4-cyanobiphenyl compounds (5OCB-d₂) and (1OCB-d₃) deuterated in the {α} and methyl positions, respectively, provide for two different NMR measurement time scales to examine effects of the self-diffusion of the molecules confined to droplets. It is found that the line shape of the spectra depends on several factors which include self-diffusion, size, shape of the droplets, and type of anchoring on the droplet walls. Theoretical director configurations calculated for spherical and nonspherical droplets in the presence of an external field were used to simulate NMR spectra in the presence of self-diffusion. Effects due to external fields present during sample preparation are discussed.
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Golemme et al. (1988) studied this question.