Dynamics of charge transfer in molecular switches II. Effective potentials and Coulomb interaction

The charge transport on a single conducting polymer chain, with impurity molecules working as switches, is investigated. The dynamics of solitons through the sites that work like a switch is numerically studied using the Su—Schrieffer—Heeger model extended to include short-range Coulomb interactions. The time-dependent unrestricted Hartree—Fock approximation is used. The considered molecular switches are single and pairs of donor—acceptor molecules bonded to the chain. The influence of the parameters of the molecules on the charge transport and the role of the length of separation between the sites where the donor and acceptor molecules bond are determined. The effects of the inclusion of short-ranged Coulomb interactions are analyzed. We write effective potentials determining the soliton behavior for each case, where the switching sites allow the soliton to pass, be reflected or trapped.