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The quantitative
G.N.Lewis Model

  Ernst Schumacher, University of Bern
  Prof.em of Chemistry, Dep. Chemistry
  and Biochemistry

  This site presents a quantitative
  Lewis model
of molecular structure,
  using G.E. Kimball's free [spherical
  electron probability] clouds

  Note: Drawings of "electron clouds" or
  "orbitals" on a molecular skeleton in
  any approximation represent helpful
  visualizations, not the "truth"! The
  same holds for the not existing
  "bonding sticks" and the arbitrary

  Gallery of examples

Orbital surfaces are the set of points at a selected amplitude of the spatial wavefunction φ, which is unlimited. Computed by Gaussian03™, drawn by WebMO™. Cores are arbitrary. ⟨φ|φ⟩ would show density surfaces (like those at right) of similar shape.

Kimball's free [electron probability] clouds are simple computational tools, explained in these pages. Their surface is the set of points at the expected radius ⟨φ|r|φ⟩ of an unlimited equilibrium s-type density distribution for every sphere (Tutorials). [He] cores are computed, too. Program from ES with Mathematica™.

The potential energies of the nuclear-electron attraction, Vne, and electron-electron repulsion, Vee, have nearly the same values for the two charge distributions.