Changing the structure from norbornane to smaller bicyclic species dramatically increases the singlet-triplet energy gap through pyramidalization of the branching carbon. Natural Bond Orbital (NBO) analysis confirms the expected presence of a lone pair on the carbanion localized at the branching carbon. The analysis further demonstrates that increasing the degree of pyramidalization from structure 1 to 3, Figure , leads to a progressive increase in the s-orbital contribution to the lone-pair orbital. Specifically, the s-orbital contribution rises from 26.5% in 1aF to 34.7% in 2a, and further to 46.7% in 3a. This trend aligns with a shift in the hybridization of the lone pair from sp³ to sp² and eventually to sp. The extent of π-donation from the phenyl rings to the cationic center can be quantified by evaluating the electron delocalization between the cationic center and the adjacent atom on the phenyl ring. Electron delocalization serves as a robust metric within the framework of quantum theory of atoms in molecules (QTAIM) , providing a measure of covalency based on the number of electrons shared between two atoms. The delocalization indices between the cationic center and the adjacent atom on the phenyl substituent for 1aF, 2a, and 3a are 1.52, 1.45, and 1.48, respectively, indicating a bond order of approximately 1.5. This finding aligns with the expectation of strong electron donation to the carbocation via phenyl groups. To further validate this conclusion, we analyzed 2-propyl cation substituted with a para-dimethylamino phenyl group (substituent a in Figure ). The natural atomic charge of this cation was calculated to be 0.32, consistent with the range of charges observed in our model systems. Furthermore, the delocalization index of the corresponding carbon pair in this cationic model was also 1.45, consistent with the other model systems. On the other hand, the delocalization index between the carbanion and carbocation centers in 1aF, 2a, and 3a are 0.98, 1.05, and 0.95, respectively. These values are within the range of ordinary single (σ) carbon-carbon bonds and consistent with the computed bond lengths between carbocation and carbanion centers for 1aF, 2a, and 3a that are 1.514, 1.500, and 1.538 Å, respectively.