The set of molecules chosen for the study are πconjugated systems that increase systematically in size, with 40, 54, and 68 electrons. The systems are characterized by a dimethyl amide donor moiety, (CH 3 ) 2 N, attached to a series of unsaturated, π-conjugated hydrocarbon chains increasing in length, (CH = CH) n H (n=1, 2, 3), acting as the electron-accepting moieties (Fig. ).