All minima and transition states were verified to have exclusively real frequencies and one imaginary frequency, respectively. Partial charges presented throughout were calculated with the Natural Population Analysis (NPA) method from the default NBO v3.1 module 59 in Gaussian. Mutliwfn v3.8 60 was used to extract atomic contributions to the Kohn-Sham (KS) orbitals according to the Mulliken partitioning scheme. All molecular renderings were made with the ChemCraft v1.8 visualization software.