Atoms and bonds in molecules: Molecular radial energy densities

The molecular radial density ( ρ rad ) serves as a powerful tool to partition molecules into: non-bonding, core, and bonding regions. Similar to ρ rad , a method is presented where both forms of the radial kinetic, exchange, Coulomb, and electron-nuclear potential energy densities are plotted on a mesh. As far as we are aware, this is the first time expressions for energy densities have been presented. Such plots provide an alternative approach to understanding the physics and chemistry of molecular properties and make it possible to partition molecular energies into atomic and bonding regions (ABIM) using any weighting function.