Visualizing and Quantifying Interactions in the Excited State

Determining the location and nature of the electron pairs within a molecule provides an intuitive representation of electronic structures. Yet, most of the available theoretical representations are not suitable for describing excited state phenomena. The Density Overlap Region Indicator (DORI) scalar field, which depends only on the density and its derivatives, overcomes previous limitations, while keeping the intuitiveness of popular scalar fields. We here demonstrate its usefulness by pinpointing visual and numerical DORI signatures for both intra- and intermolecular excited state situations.