The last example to be considered belongs purely to main-group chemistry and does not include any metal atoms. From Figure , we can expect that the artifact might appear for the carbon atom when CN C transitions from 3 to 4. We needed to select an example where, along the C-C bond stretch coordinate, the PES would be flat enough to be sensitive to the bumps in dispersion energy when the DFT and D3 energies are summed. Therefore, we chose a dispiro(acridan)-substituted pyracene (DSAP) molecule, which has a remarkably long single C-C bond (Figure ). As expected, we found two local minima in this case, and the DSAP-( ) minimum disappears if the dispersion correction is turned off.