Similar to the neutral diradical state, the electron and charge in the radical cation state of cg-2 are also spatially segregated (i.e., the electron is distributed on one half, and the positive charge is distributed on the other half). This unique electronic property of the radical cation state of cg-2 is also predicted by DFT calculated spin density distribution and electrostatic potential surface (Fig. ). cw-EPR spectrum of the radical cation state of cg-2 was measured in frozen CH2Cl2 at 153 K to suppress the rapid tumbling motion in solution. The signal is split into a quintet by four anisotropic protons with simulated hyperfine coupling constants of aH = 0.40, 0.39, 0.43 and 0.52 mT (Fig. ). This observation provides direct experimental evidence for the spatially segregated spin in the radical cation state of cg-2, because if the spin is globally delocalized over the whole molecule, the EPR signal will be split into a nonet by eight anisotropic protons, each with the halved aH. It should be noted that as the temperature increases, a nonet EPR signal appears, probably due to the averaging effect caused by tumbling motion or by thermally populated electron hoping from one half to the other half (Supplementary Fig. ). The dication state of cg-2 recovers its closed-shell electronic structure, therefore the 1 H NMR measurement was performed. The protons Ha and Hb appear at downfield region (Fig. ), indicating the deshielding effect brought by the presence of positive charge.