Two Dimensional NMR Time Evolution Correlation Spectroscopy in Liquid Crystals

Two dimensional NMR time evolution correlation spectroscopy, where a correlation of NMR relaxation and line-shapes are performed, provides a powerful tool in characterization of systems involving two or more spin groups. This technique is applied to proton NMR study in liquid crystal para-azoxy anisole in the nematic phase at two different frequencies. Two different spin groups corresponding to methyl and phenyl protons are identified, as expected. The methyl proton spin lattice relaxation time shows a greater frequency dependence compared to phenyl protons.