3D ED is an emerging new technique that opens up a new world of structure determination of small molecules and proteins. The technique is fast and reliable complementing the use of X-rays when the limiting factor is the size of the the crystals for structure determination.

3D ED provides Atomic details extracted from individual submicro-sized crystals (<200 nm in size), even in a heterogeneous mixture of submicrocrystalline powders. 3D ED data is acquired on a transmission electron microscope (TEM), using electrons as the incident beam.

Gruene, T. et al. Rapid Structure Determination of Microcrystalline Molecular Compounds
Using Electron Diffraction. Angew. Chemie – Int. Ed. 57, 16313–16317 (2018).

Another important feature of electron scattering is that the diffraction pattern formed by elastically scattered electrons yields Coulomb potential maps rather than electron density maps providing a unique method to visualize the charged states of metals and amino acid residues.

Yonekura, K., Kato, K., Ogasawara, M., Tomita, M. & Toyoshima, C. Electron crystallography of ultrathin 3D protein crystals: Atomic model with charges. Proc. Natl. Acad. Sci. U. S. A. 112, 3368–3373 (2015)