A solar cell is described that comprises: (a) a semiconductor charge
separation material; (b) at least one electrode connected to the charge
separation material; and (c) a light-harvesting film on the charge
separation material, the light-harvesting film comprising non-covalently
coupled, self-assembled units of porphyrinic macrocycles. The porphyrinic
macrocycles preferably comprise: (i) an intramolecularly coordinated
metal; (ii) a first coordinating substituent; and (iii) a second
coordinating substituent opposite the first coordinating substituent. The
porphyrinic macrocycles can be assembled by repeating intermolecular
coordination complexes of the metal, the first coordinating substituent
and the second coordinating substituent.