Exciton and Electron Interaction in Covalently-linked Dimeric Porphyrins

The interactions between dimeric porphyrins I (n = O-8), covalently linked at their peripheries, were measured from their electronic absorption spectra and 13C NMR spectra. For I (n less than 2), interactions between the 2 rings are observed; for I (n greater than 2), the interactions decrease.