Direct determination of the absolute electron density of nanostructured and disordered materials at sub-10-nm resolution

We report the development of a novel experimental approach to the direct determination of the absolute electron density of nanostructured and disordered materials. By calibrating the incident coherent x-ray flux and the diffraction pattern intensity and using the oversampling method, we have directly determined the absolute electron density of a porous silica particle at ~9-nm resolution. This general approach can be used for the quantitative characterization of nanocrystals and noncrystalline materials at nanometer or better resolution.