Chemical binding and electron correlation effects in x-ray and high energy electron scattering

The total, inelastic and elastic intensities for x-ray and high energy electron scattering from the ten-electron molecules CH4, NH3, H2O, and HF have been calculated with configuration interaction wave functions. The probability density of the interelectronic distance or the radial intracule density is extracted from the intensities. The importance of basis sets, chemical binding, and electron correlation to the scattered intensities and the radial intracule density has been examined. It has been found that scattered intensities predicted with correlated wave functions agree well with experiment. Based on the electron pair distribution, the exchange and correlation holes in molecular systems have been briefly discussed.