Dynamical simulation of exciton dissociation in poly(para-phenylenevinylene) systems

We report results from simulations of field-induced exciton dissociation in poly(para-phenylenevinylene) (PPV). The simulations were performed by solving the time-dependent Schrödinger equation and the lattice equation of motion simultaneously and non-adiabatically. The electronic system and the coupling of the electrons to the lattice were described by an extended three-dimensional version of the Su-Schrieffer-Heeger (SSH) model. The dissociation time is shown to depend strongly on the field strength as well as on the excitation energy and the lattice energy. The separation process is highly non-adiabatic and involves a significant rearrangement of the electron distribution.