The bridge between QTAIM and other branches of experimental and molecular and condensed phase sciences rests largely on its ability to produce atomic regional properties that can be readily compared to other results . Well-defined regional energies are a quality of any volume bounded by zero flux surfaces. Taking this property to the limit, the gradient bundle decomposition method is the differential partitioning of 𝜌 into infinitesimal zero-flux surface bounded regions used to compute, using 𝜌 and other scalar fields, the gradient bundle condensed energy, charge density, and other condensed properties. The topology of the condensed charge density also defines the surfaces of unique charge density bonding regions called bond bundles.