Corrected zero-point vibrational energies (ΔZPEs), electronic enthalpy variations (ΔH⁰_elec) going from the pristine model CPDT-BT-CPDT moiety to the protonated one. Proton affinities (P(A)) calculations for different protonating sites, as highlighted in the sketch below, were performed in gas-phase. All values in the table are expressed in kcal mol⁻¹.

	ΔZPE	ΔH0elec	P(A)
1	7.22	−237.70	231.96
2	7.06	−229.51	223.94
3	6.67	−232.95	227.76