Electron Shells of Periodic Table Elements Visualized by Localized Orbital Locator: Analyzing the Atom’s Structure and Properties

All electron shells of 118 elements of the periodic table are visualized using the parameters of the (3,-3) critical points in the topology of the localized orbital locator function, and a consistent compression of shells with increasing atomic number (Z) is demonstrated. A relationship is established between the properties of atoms (atomic size, ionization energy, electronegativity) and the parameters of the (3,-3) critical points of the outer shell. This interconnection allows scanning of activity centers, analysis of reactivity, and local properties of atoms in molecules via parameters of the (3,-3) critical points. Based on the parameters of the (3,-3) critical points as electronegativity descriptors, a ranking of 24 known electronegativity scales is performed for the sp-, d-, and f-blocks of the periodic table elements. Using these descriptors, a correction of the Pauling electronegativity scale is carried out to obtain new electronegativity values. The parameters of the (3,-3) critical points provide a digital visualization of phenomena such as the relativistic contraction of electron shells, as well as the lanthanide and actinide contraction, at the level of all electron shells.