The 2,2 ′ ,6,6 ′ -tetrahydro-4H,4 ′ H-5,5 ′ -spirobi[cyclopenta-[c]pyrrole] cation, which we call the spiro cation, is a mixed-valence molecule with two subsystems that share a central, bridging carbon. Due to the Jahn-Teller effect, the cation hole is either partly localized on the left or right ring. The spiro cation structure is shown in Figure . Letting R and R denote the coordinates where the hole is localized on the left and right respectively, we consider a linear synchronous path from structure (1) → structure (2), and structures along the path given by