Proton migration appears to be most favorable along the ultra-short hydrogen bonds, i.e., from pyrrole A to B, or vice versa, or from pyrrole C to D, and vice versa. Exceedingly low activation energies (electronic energies) are associated with these migrations, only about a quarter to a third of an eV (6.5-7.5 kcal/mail) relative to the trans ground state. Again, for comparison, the activation barrier for proton migration is ~12 kcal/mol for the conjugate base of free-base porphine and ~16 kcal/mol for neutral free-base porphine. In contrast, much higher activation energies, on the order of an eV (23 kcal/mol), are associated with proton migration between rings A and D and between rings B and C of H2Cor -.