The measurement of charge densities by diffraction techniques

Abstract

A brief review of the field of the determination of information on atomic and molecular charge densities by electron scattering is presented. The connection between this work and x-ray scattering is pointed out. Recent calculations on atomic charge densities for the neon atom are reviewed and compared with new experimental data. It is shown that current experimental techniques are on a par with a CI wave function for Ne, giving 86% of the electronic correlation energy, for deducing information about detailed shapes of the charge distribution in small atoms and molecules. Recent calculations of scattered molecular intensities with molecular wave functions are reviewed and compared with existing experimental data. It is pointed out that effects of correlation and chemical binding on charge densities can probably be investigated currently with greater accuracy by experimental techniques than with presently available numerical theoretical procedures in the case of many molecules.