of their respective total changes-for example, the C1-C2 bond, which loses 1.1 electrons through the reaction, has lost 0.28 of these at the TS. In contrast, the forming C⋯C bonds initially change less rapidly. Over the course of the reaction these bonds gain 1.97 electrons, but only 0.31 of these at the TS (16%). QTAIM originated from Bader's prescient question, "Where are the atoms in molecules?"