Cinematic Molecular Science Explored by High-Speed Electron Microscopic Video Imaging

Single-molecule atomic-resolution time-resolved electron microcopy (SMART-EM) with a high-speed, high-resolution transmission electron microscope has ushered in the era of "cinematic molecular science", in which the dynamic behavior of organic and inorganic molecules can be studied through real-time video images [1, 2]. High speed imaging without increase of electron dose results in very low electron dose per frame, which often causes a very low signal to noise ratio. We have established a method to improve the image quality optimized for SMART-EM by applying the Chambolle Total Variation (CTV) denoising, which enables tracking of molecular motion with sub-millisecond temporal resolution and sub-angstrom localization precision [3]. Herein we demonstrate in-situ observation of a nanomechanical shuttling motion of a single molecule [4], and cascade reactions of nanocarbons [5,6], as applications of the high-speed SMART-EM. We also introduce a new molecular model, atomic-number-correlated (ZC) molecular model, designed for spreading the microscopic molecular imaging to chemists who are still unfamiliar to electron microscopy [7].<br/>References<br/>[1] E Keinan, AsiaChem <b>2</b> (2021), p. 96.<br/>[2] E Nakamura, Acc. Chem. Res. <b>50</b> (2017), p. 1281.<br/>[3] J Stuckner et al., Microsc. Microanal. <b>26</b> (2020), p. 667.<br/>[4] T Shimizu et al., Bull. Chem. Soc. Jpn. <b>93</b> (2020), p. 1079.<br/>[5] T Shimizu et al. J. Am. Chem. Soc. <b>144</b> (2022), p 9797.<br/>[6] D Liu et al. Proc. Natl. Acad. Sci. U.S.A. <b>119</b> (2022) e2200290119.<br/>[7] J Xing et al. Proc. Natl. Acad. Sci. U.S.A. <b>119</b> (2022) e2114432119.