Molecular architecture: The optical treatment of dark field electron micrographs of atoms

Abstract

Light optical techniques, including high and low spatial frequency filtering and superposition of images, have been applied to dark field electron micrographs of uranium, platinum, iodine, and palladium atoms in small model molecules, and osmium atoms bound to DNA. Contrast in the images is increased and the signal to noise ratio enhanced. The improvement for a series of images of one small molecule is so great that substructures of the molecule are revealed, substructures consisting of groups of atoms as light as arsenic and carbon that are completely masked by noise in the untreated images. These results corroborate that images of single atoms are seen in the original micrographs.