9623777 Richardson The theme of the proposed work is to examine the consequences of the very large amplitude quantum motion in solid helium. The first objective is to observe and measure the rates of exchange of 3He atoms in three, four, and six particle rings. According to theory, the ring-like exchange motion is responsible for the unique nuclear magnetic ordering in solid 3He. The ring exchange motion has never been directly observed. Special nmr techniques will have to be developed for the observation. A further objective of the work is an attempt to see new modes of atomic motion by using Magnetic Resonance Imaging. Several unusual and important phenomena have been predicted but have never been observed. %%% The researchers will use nuclear magnetic resonance techniques to study a remarkably interesting material, solid helium. Because helium has such a very light mass, its atomic motion is quite large even near absolute zero temperature. Modern magnetic resonance techniques will be used to study the nature and consequences of that motion. For example, the zero temperature state of solid helium has been predicted to have the atoms moving rapidly in ring like rotations, rather than sitting quietly at fixed crystalline lattice points. ***