On bond-critical points in QTAIM and weak interactions

Bond critical points (BCPs) in the quantum theory of atoms in molecules (QTAIM) are shown to be a consequence of the molecular topology, symmetry, and the Poincar,-Hopf relationship, which defines the numbers of critical points of different types in a scalar field. BCPs can be induced by a polarizing field or by addition of a single non-bonded atom to a molecule. BCPs and their associated bond paths are therefore suggested not to be a suitable means of identifying chemical bonds, or even attractive intermolecular interactions.