Face-to-face stacks of PTCDA molecules in films and multiple quantum wells are modeled using Frenkel and charge-transfer excitons that are coupled to a characteristic molecular vibration. The intensity and vibronic structure of film fluorescence are extensions of the mixed Frenkel-CT model for absorption and electroabsorption. Ab initio relaxation energies of PTCDA excited states and molecular ions provide independent estimates of model parameters, while the (pi) - (pi) * transition dipole gives the hopping integral J. PTCDA's close connections to conjugated hydrocarbons and its structural and electronic simplicity are emphasized.

Date Published: 17 December 1999
PDF: 12 pages
Proc. SPIE 3797, Organic Light-Emitting Materials and Devices III, (17 December 1999); doi: 10.1117/12.372700

Published in SPIE Proceedings Vol. 3797:
Organic Light-Emitting Materials and Devices III
Zakya H. Kafafi, Editor(s)