Ultrafast charge transfer in phytochlorin–[60]fullerene dyads: influence of the attachment position

A femtochemistry study has been performed on two phytochlorin–[60]fullerene donor–acceptor dyads, in which the fullerene moiety is linked via a pyrrolidine bridge either to the position 3 or 7 of the phytochlorin ring. Both dyads form an emissive intramolecular exciplex in less than 1 ps, but only the former dyad relaxes to the ground state via a charge transfer (CT) state.