Abstract
Density functional theory (DFT) approaches based on range-separated hybrid functionals are currently methods of choice for the description of the charge-transfer (CT) states in organic donor/acceptor solar cells. However, these calculations are usually performed on small-size donor/acceptor complexes and as result do not account for electronic polarization effects. Here, using a pentacene/C60 complex as a model system, we discuss the ability of long-range corrected (LCR) hybrid functionals in combination with the polarizable continuum model (PCM) to determine the impact of the solid-state environment on the CT states. The CT energies are found to be insensitive to the interactions with the dielectric medium when a conventional time-dependent DFT/PCM (TDDFT/PCM) approach is used. However, a decrease in the energy of the CT state in the framework of LRC functionals can be obtained by using a smaller range-separated parameter when going from an isolated donor/acceptor complex to the solid-state case.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2616-2621 |
| Number of pages | 6 |
| Journal | The Journal of Physical Chemistry Letters |
| Volume | 7 |
| Issue number | 13 |
| DOIs | |
| State | Published - Jun 28 2016 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): N62909-15-1-2003
Acknowledgements: The authors are most indebted to Dr. Leeor Kronik for very
stimulating discussions. We gratefully acknowledge financial support of this work at
the Georgia Institute of Technology by the Department of the Navy, Office of Naval
Research (Award No. N00014-14-1-0580), and by King Abdullah University of
Science and Technology (V.C.). The work at King Abdullah University of Science
and Technology has been supported by KAUST competitive research funding and the
Office of Naval Research – Global (Award No. N62909-15-1-2003).