Eur. Phys. J. B (2013) 86: 66
https://doi.org/10.1140/epjb/e2012-30592-1

Regular Article

Exciton properties of selected aromatic hydrocarbon systems^*

¹ IFW Dresden, P.O. Box 270116, 01171 Dresden, Germany
² Institute of Physics of Complex Matter, Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne, Switzerland
³ Institut für Festkörperphysik, Technische Universität Dresden, 01062 Dresden, Germany

^a e-mail: f.roth@ifw-dresden.de

Received: 13 July 2012
Published online: 20 February 2013

Abstract

We have examined the singlet excitons in two representatives of acene-type (tetracene and pentacene) and phenacene-type (chrysene and picene) molecular crystals, respectively, using electron energy-loss spectroscopy at low temperatures. We show that the excitation spectra of the two hydrocarbon families significantly differ. Moreover, close inspection of the data indicates that there is an increasing importance of charge-transfer excitons at lowest excitation energy with increasing length of the molecules.