论文信息 - Electron microscope contrast of small atom clusters

Electron microscope contrast of small atom clusters

Abstract The contrast for gold due to single atoms, flat clusters of 3 and 7 atoms and a double layer cluster of 19 atoms is calculated as a function of defocus including the effect of spherical aberration. The exact complex scattering factor is used and the effect of the imaginary part of the scattering factor on the image contrast is investigated for both single atoms and clusters. The calculated contrast for the double layer 19 atom cluster is found to agree with an experimental image of a gold cluster on graphite. The calculations also investigate the effect of a phase plate upon the contrast of the clusters.

C. R. Hall | R. Hines

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