Nuclear magnetic resonance of oriented fluorobenzene in a nematic potassium laurate mesophase. Distance ratios and order tensor elements

Proton-proton and proton-fluorine distance ratios and elements of the order tensor are obtained from nuclear magnetic resonance spectra of fluorobenzene partially oriented in a potassium laurate lyotropic mesophase. Corrections for harmonic vibrations are applied and it is shown that for proton-proton and proton-fluorine distance ratios corrections are significant. Errors due to weighting in the structural analysis as well as errors due to solvent dependence of the scalar couplings are investigated. These experiments show that the anisotropy in the indirect couplings after vibrations have been considered are negligible. The elements of the order tensor are discussed in terms of the orienting influence of the interface and alkyl chains of the mesophase surfactant.