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Updated: Jun 16, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Interpretation of the ultrafast photoinduced processes in pentacene thin films
Thomas S Kuhlman1, Jacob Kongsted, Kurt V Mikkelsen
1Centre for Molecular Movies, Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark. thomk@kemi.dtu.dk
Abstract:
Ambiguity remains in the models explaining the photoinduced dynamics in pentacene thin films as observed in pump-probe experiments. One model advocates exciton fission as governing the evolution of the initially excited species, whereas the other advocates the formation of an excimeric species subsequent to excitation. On the basis of calculations by a combined quantum mechanics and molecular mechanics (QM/MM) method and general considerations regarding the excited states of pentacene we propose an alternative, where the initially excited species instead undergoes internal conversion to a doubly excited exciton. The conjecture is supported by the observed photophysical properties of pentacene from both static as well as time-resolved experiments.
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