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High Resolution Transmission Electron Microscopy at Zero Cs

Published online by Cambridge University Press:  02 July 2020

Michael A. O'Keefe*
Affiliation:
National Center for Electron Microscopy, University of California, LBL B72, Berkeley, CA, 94720
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Now that correctors for objective lens spherical aberration are becoming feasible, questions have been raised about the usefulness of high-resolution transmission electron microscopy at zero Cs and the possible difficulties of interpretation of such images. In general, high resolution TEM images are interpreted either by comparison with simulations from model structures or by contrast transfer functions (CTFs) to determine the weight (and sense) of spatial contributions to images from corresponding diffracted beams. At zero Cs, HREM image simulations will work, but a projected charge density theory should be used (instead of CTF theory) to interpret images. Both theories use approximations; CTF theory relies on kinematic scattering and PCD theory on zero Cs and limited defocus.

Type
Advances in Instrumentation and Performance
Copyright
Copyright © Microscopy Society of America

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