NMR Studies of Various Solutes in a Lyotropic Mesophase

-High resolution nuclear magnetic resonance spectroscopy of solute molecules in ordered media has in the past been largely confined to the use of thermotropic liquid crystals as the solvent. A valuable alternate approach involving the use of a lyotropic mesophase was first reported by Lawson and Flautt, but has since been largely neglected. The present paper describes results of studies carried out for several diazines, furan, thiophene, p-dithiin, sodium methylphosphonate, methanol and acetonitrile. Comparisons are presented of results obtained here and in work based on the use of thermotropic media. These studies clearly demonstrate the utility of the lyotropic phase for obtaining reliable structural information. The orientations of the various solutes studied over a range of temperatures depend not only on molecular shape, but specific solute-solvent interactions.