9312544 Golding The aim of this experimental and theoretical research project is to achieve a detailed, microscopic description of the motion and energetics of defects that hop or tunnel between two closely spaced sites in metals. Interest in defect dynamics has assumed significance recently for fundamental as well as technological reasons. Experimental tools, such as lithographic techniques, are being developed to allow the study of a moving ion and its interactions with conduction electrons and lattice vibrations. Understanding the basic mechanism underlying these fluctuations is crucial for assessing the stability and reliability of material for submicron structures and devices. The project theorist co- principal investigator is at AT&T Bell Laboratories. %%% ***