ABSTRACT
As discussed in Chapter 5, spin-spin exchange interaction has a signicant effect on the main properties of various polymer:fullerene composites. Since charge carriers in conjugated polymers and their composites have spins, this feature can be used for the creation of spintronic devices with spin-assisted electronic properties [36]. In such devices, positive charge on polymer chain (polaron/hole) exchangeable spin-ips negative charge on fullerene, so the further charge recombination becomes dependent on their dynamics, number, polarization, and mutual separation. For large separations, when thermal energy exceeds the interaction potential, the charges are considered as noninteracting. Once the carriers become nearer than the inverted Coulombic interaction potential, their wave functions overlap and exchange interactions become nonnegligible. This can lead to the formation of singlet or triplet excitons in organic semiconductors.
