Quantitative analysis of the electrostatic potential in rock-salt crystalsusing accurate electron diffraction data

Very accurate electron structure factors measured by a significantly improv ed transmission electron diffraction technique for polycrystalline samples were used in a high-resolution quantitative study of the electrostatic pote ntials in LiF, NaF, and MgO crystals. The spatial electrostatic potential d istribution was obtained using an analytical structural kappa -model adapte d for electron diffraction. A topological analysis of the electrostatic pot ential, defining the features of the electrostatic field and the Coulomb fo rce field in a crystal was developed. In addition to the topological analys is of the electron density, this approach provides a more complete descript ion of the atomic interactions. The application of this approach to the cha racterization of bonding in a crystal has been demonstrated. The suitabilit y of electron diffraction for determination of the core-electron binding en ergy is discussed.