This work is concerned with the quantitative characterization of materials at the highest levels of spatial resolution. This award will be used to purchase an imaging energy filter, which will be added to a high- resolution transmission electron microscope. The addition of such a filter will open the path to many new observation modes such as elastic bright field imaging, electron spectroscopic imaging and diffraction and electron spectroscopic convergent beam electron diffraction. The filter is to be mounted after the microscope lenses and hence all previously available observation modes will remain accessible. The filter will permit researchers to obtain chemical information at near atomic resolution. Among the projects which will benefit from the energy filter are: extension of the point resolution of the existing instrument down to the information limit by means of energy filtering and wave function retrieval techniques, analysis of the structure of fullerene nanotubes and magnetic nanocrystals, determination of the degree of Cr-segregation in Cobalt alloy thin films used for magnetic recording, in-situ observations of the formation of titanium disulfide platelets from sulfides, in-situ observation of diffusion processes in polycrystalline films, and characterization of the chemical structure of pressure-induced amorphous phases. %%% Quantitative characterization of materials requires not only a complete crystallographic description of the structure, but also a detailed chemical understanding of all defects and internal interfaces at the highest levels of spatial resolution. The addition of this imaging filter to the transmitting electron microscope will permit researchers to obtain chemical information at near atomic resolution for technologically-important materials such as crystalline, quasi-crystalline and amorphous solids, fullerene nanotubes and magnetic nanocrystals, and alloy thin films used for magnetic recording.