Charge density determination by X-ray diffraction

Abstract

Abstract Many aspects of the chemical bond and molecular structure are directly related to the electron density which can be determined by advanced theoretical and experimental techniques. Each method has its own advantages and limitations and their applicability is subject to different conditions. The molecular electron distribution continuously rearranges itself due to the motion of the nuclei. Under certain assumptions the averaged dynamic distribution is deducible from the static density of the equilibrium structure. The X-ray is scattered by the electrons and the diffracted intensity is related to the electron distribution. The simplest theory applied to interpret the measurement states that the time averaged scattering is dominated by the scattering from the thermally averaged distribution. The observed data are limited and their interpretation must involve modelling.