NMR of deuterium in liquid crystal mixtures

Abstract

Deuterium NMR spectra of D2 dissolved in mixtures of the nematic liquid crystals N-(p-ethoxybenzylidene)-p′-n-butyl-aniline and Merck ZLI 1132 are discussed in terms of a theory based on the interaction of the molecular quadrupole moment with the average electric field gradient. The average field gradient depends upon the liquid crystal composition and hence can be adjusted to various values (including zero) between those of the pure liquid crystals. It is shown that for deuterium dissolved in these phases the molecular quadrupole—average field gradient mechanism can account for most but not all of the orientational ordering.