Ultrafast electron diffraction and electron microscopy: present status and future prospects
E.A. Ryabovb aLomonosov State University of Fine Chemical Technologies, prosp. Vernadskogo 86, Moscow, 119571, Russian Federation bInstitute of Spectroscopy, Russian Academy of Sciences, ul. Fizicheskaya 5, Troitsk, Moscow, 108840, Russian Federation cInstitute on Laser and Information Technologies, Russian Academy of Sciences, Svyatoozerskaya str. 1, Shatura, Moscow Region, 140700, Russian Federation
Acting as complementary research tools, high time precision spectroscopy and diffractometry techniques using various physical principles open up new possibilities for studying matter with necessary integration of the “structure—dynamics—function” triad in physics, chemistry, biology and materials science. Since the 1980s, a new field of research has started at the leading research laboratories, aimed at developing means of filming the coherent dynamics of nuclei in molecules; and fast processes in biological objects (“atomic and molecular movies”). The use of ultrashort laser sources has significantly modified traditional electron beam approaches to and provided high space-time resolution for the study of materials. Diffraction methods using frame-by-frame filming and the development of the main principles of the study of coherent atomic dynamics have provided insights into wave packet dynamics, the dynamics of the intermediate states of reaction centers, and that of electrons in molecules, thus allowing the transition from the kinetics to the dynamics of the phase trajectories of the molecules in the investigation of chemical reactions.