Polarization energies, transport gap and charge transfer states of organic molecular crystals
Z.G. Soos and E.V. Tsiper
Department of Chemistry, Princeton University, Princeton, NJ 08544
A self-consistent calculation of electronic polarization in organic
molecular crystals and thin films is presented in terms of charge
redistribution in nonoverlapping molecules in a lattice. The
polarization energies P+ and P- of a molecular cation and anion are
found for anthracene and perelynetetracarboxylic dianhydride (PTCDA),
together with binding energies of ion pairs and transport gaps of
PTCDA films on metallic substrates. The 500 meV variation of (P+)+(P-)
with film thickness agrees with experiment, as do calculated
dielectric tensors. Comparisons are made to submolecular calculations
in crystals.