Electron Diffraction Imaging of Carbon Monoxide via K-Shell Ionization by Compton Scattering of 20 keV Photons.

We report theoretical momentum distributions of electrons ejected from the C and O K shells of fixed-in-space CO molecules by Compton scattering of 20 keV photons for different magnitudes and orientations of the photon momentum transfer with respect to the molecular axis. We observe distinct diffraction patterns in our computed momentum distributions, which are governed by the interference of the direct Compton electrons and those which are scattered on the parent and neighboring nuclei. The observed phenomenon is similar to that employed in diffraction imaging using high-energy photoelectrons. It persists after integration over different magnitudes and the orientation of the photon momentum transfer in the molecular frame of reference. A corresponding coincidence experiment confirms our theoretical predictions.