A MODEL DESCRIPTION OF CHARGE CARRIER TRANSPORT PHENOMENA IN ORGANIC MOLECULAR-CRYSTALS .2. PERYLENE

A model description, previously used for computer simulation studies of charge carrier transport phenomena in polyacene crystals, has been extended to alpha-perylene crystals. A modified Sano-Mozumder (SM) model has been used for simulation of reported experimental carrier transport characteristics as a function of electric field E and temperature T, both in the hot and in the thermalized carrier regime. The present studies demonstrate the plausibility of a nearly small molecular polaron (MP) model approach to describe phenomenologically the negative charge carrier separation and transport phenomena in alpha-perylene crystals over a wide temperature (30-300 K) and electric field (10(3)-10(5) V/cm) range. On the other hand, the behaviour of positive charge carrier transport characteristics in alpha-perylene indicates small lattice polaron (LP) formation.