Among the studied species only in 2a and 3a the singlet state remains notably lower than the triplet states in the gas phase. Interestingly, the singlet-triplet gap in 2a and 3a switch and 2a in the gas phase sustains a larger singlet-triplet gap. NBO analysis and inspecting the geometry of 2a reveal that while, the branching carbon is negatively charged (q(Cb) = -0.35) the σ-framework of the molecule is distorted in a way that now a polarized double bond is formed between the formal carbanion and carbocation, characterize local minima. To evaluate the impact of different functionals on the results, all local minima were reoptimized using the M06-2X , B3LYP , and BLYP functionals with the same basis set. The results obtained with M06-2X and B3LYP were quantitatively similar to those of ω-B97XD, while GGA-BLYP predicted significantly larger singlet-triplet gaps. All density functional theory (DFT) computations were carried out in both the gas phase and in N,Ndimethylformamide (DMF) as a solvent, using the SMD solvation model. The quality of openshell DFT computations for triplet states was assessed by examining spin contamination, and all unrestricted DFT (UDFT) results were confirmed to be free of significant spin contamination as spin-squared operator values for triplet states remain close to 2, Table .