title: 4D ultrafast electron diffraction, crystallography, and microscopy.
abstract: In this review, we highlight the progress made in the development of 4D ultrafast electron diffraction (UED), crystallography (UEC), and microscopy (UEM) with a focus on concepts, methodologies, and prototypical applications. The joint atomic-scale resolutions in space and time, and sensitivity reached, make it possible to determine complex transient structures and assemblies in different phases. These applications include studies of isolated chemical reactions (molecular beams), interfaces, surfaces and nanocrystals, self-assembly, and 2D crystalline fatty-acid bilayers. In 4D UEM, we are now able, using timed, single-electron packets, to image nano-to-micro scale structures of materials and biological cells. Future applications of these methods are foreseen across areas of physics, chemistry, and biology.
authors.affiliation: Laboratory for Molecular Sciences and Physical Biology Center for Ultrafast Science and Technology, California Institute of Technology, Pasadena, California 91125, USA. zewail@caltech.edu
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Zewail
mesh_terms: D000818:Animals; D003461:Crystallography / Q000295:instrumentation / Q000379:methods*; D004247:DNA / Q000737:chemistry; D004583:Electrons; D005227:Fatty Acids / Q000737:chemistry; D008854:Microscopy, Electron / Q000295:instrumentation / Q000379:methods*; D008958:Models, Molecular; D011506:Proteins / Q000737:chemistry; D012542:Scattering, Radiation
chemical_list: D005227:Fatty Acids; D011506:Proteins; D004247:DNA