Atomistic and mesoscopic modelling of electric charge evolution in polymers

Abstract

We address some of the issues relating to charge transport in polymer based devices. We examine the effects of variable chain length on both intramolecular and intermolecular bipolar charge transport in polydiacetylene (PDA) and poly(para-phenylenevinylene) (PPV), which should apply more widely to other polymer systems. Self-consistent quantum molecular dynamics calculations have been used to provide information on charge transport properties of individual polymer strands. Generalised Monte-Carlo calculations, with specific description of the ensemble of polymer strands, have been used to assess the effects of texture on the competition between charge transport, trapping and recombination across the polymer slab. Our results show an unanticipated but important effect from relatively long-lived yet transient trapping.