Quantum Theory of Atoms in Molecules

Abstract The proposition of a modern atomic dimensionality should be laureate to the pioneering spirit of the theoretician in physics and chemistry, Richard Bader. By taking into account the electronic-density as a pure and physical variable, Bader has formulated a mathematical protocol for modeling the charge density fluxes on the molecular surfaces. To this end, he also assumed the atomic environment as being an open space suitable for exchange charge and momentum with the neighbors around it. The integration of the molecular surface is ruled by the virial theorem embodied by the contributions of the kinetic and potential energy densities, wherein, both of them are represented by the Laplacian field of the electronic density.