Electron crystallography--accomplishments and challenges

Electron crystallography is a powerful tool for the quantitative structural characterization of substances that preferentially form thin microcrystals. Because multiple-beam dynamical scattering may cause observed diffraction intensities to deviate significantly from their kinematical values, it is necessary to demonstrate that the conditions favoring ab initio determinations can be established. Review of similar determinations made from electron and X-ray data make clear both the strengths and weaknesses of electron crystallography. With current instrumentation, the major onus now placed on the experimentalist is to optimize specimen preparation so that the resultant diffraction data can be directly interpreted.