摘要:
The deuterium and proton NMR spectra of samples of 4-ethoxy-4'-cyanobiphenyl dissolved in the nematic liquid crystal 4-hexyloxy-4'-cyanobiphenyl have been analyzed to yield quadrupolar splittings and dipolar couplings. The data are compared with values calculated for three models for the conformations adopted by the ethoxy group relative to the attached phenyl ring. These models are (a) a set of four, symmetry-related structures, (b) discrete, minimum-energy structures generated by jumps about the C4-O, O-C-7, and C-7-C-8 bonds, and (c) the same as (b) except that a continuous potential is adopted for the motion about the O-C-7 bond.