Momentum dependence of the excitons in pentacene.
We have carried out electron energy-loss investigations of the lowest singlet excitons in pentacene at 20 K. Our studies allow to determine the full exciton band structure in the a∗, b∗ reciprocal lattice plane. The lowest singlet exciton can move coherently within this plane, and the resulting exciton dispersion is highly anisotropic. The analysis of the energetically following (satellite) features indicates a strong admixture of charge transfer excitations to the exciton wave function.
IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany.
Friedrich
F
Roth
Roman
R
Schuster
Andreas
A
König
Martin
M
Knupfer
Helmuth
H
Berger