Nature of Chemical Interactions from the Profiles of Electron Delocalization Indices

We analyze the behavior of the profiles of delocalization indices (DIs) between relevant pairs of atoms along reaction coordinates for a set of model chemical processes. A relationship between the topology of the DI and the nature of the underlying chemical change is reported. As shown, exponential shapes correspond to the traditional category of repulsive/nonbonded interactions, while sigmoidal profiles signal the formation/breaking of chemical links.