A Reinvestigation of Small-angle Electron Scattering by CS2 and CCl4 Molecules

A small-angle electron-diffraction unit (Jpn. J. Appl. Phys., 11, 1199 (1972)) has been improved by enlarging the scattering chamber and installing a new nozzle system and a better counting unit. The intensities of 50 keV electrons scattered by CS2 and CCl4 molecules have been measured with a ≈1% precision in the s-range from 1 to 11.5 Å−1. Theoretical intensities have been calculated for the independent-atom model by taking into account the intramolecular double-scattering effect, and those intensities have been compared with the experimental intensities. The oscillatory feature appearing in the difference function, Δσ(s)=s4(Iexptl–IIAM), of CCl4 has been ascribed mainly to the deformation of the one-electron density in chlorine atoms by chemical binding.