It is evident in Figure (a) that when the difference in monomer LUMO energies is large (~1.5-2 eV), the dimer LUMO energies begin to increase in energy relative to the LUMO acceptor monomer's LUMO energy. Figure (c) illustrates that modest differences in monomer HOMO energies (less than 1 eV) frequently result in dimer HOMO energies that decrease in energy relative to the HOMO donor monomer's HOMO energy. Increases in LUMO energies and decreases in HOMO energies after extending the conjugated 𝜋 systems contradict expected FMO energy trends. The negative HOMO shifts were much more prevalent than the negative LUMO shifts, therefore the HOMO shift trends were further explored.