NMR OF HE-3 DISSOLVED IN ORGANIC-SOLIDS

It has been found that He-3 under pressures of a few atmospheres disso lves in the solid polymers Lucite, Nylon, Delrin, polyethylene, Teflon , and Lexan sufficiently to yield strong helium NMR spectra. The peaks range from sharp (Lucite, Lexan) to relatively broad (nylon, Delrin). The signals are interpreted as indicating rapid motion among sites. H elium NMR signals were also seen in the organic polycrystalline solids benzene, durene, naphthalene, phenanthrene, tert-butyl alcohol, aceti c acid, and hexamethylbenzene. More complicated spectra with broader l ines were obtained. Changes on repeated melting and refreezing are int erpreted to indicate shift dependence on the orientation of individual crystallites. It is considered that He-3 NMR spectroscopy is likely t o yield valuable information about sites available and motion among th em in a variety of solids in the future.