Journal
JOURNAL OF CHEMICAL PHYSICS
Volume 138, Issue 11, Pages -Publisher
AIP Publishing
DOI: 10.1063/1.4794427
Keywords
-
Funding
- Center for Re-Defining Photovoltaic Efficiency through Molecule Scale Control
- Energy Frontier Research Center
- U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences [DE-SC0001085]
- U.S. Department of Energy, Office of Basic Energy Sciences [DE-AC02-98CH10886]
- Department of Energy Office of Science Graduate Fellowship Program (DOE SCGF)
- ORISE-ORAU [DE-AC05-06OR23100]
Ask authors/readers for more resources
We apply our theoretical formalism for singlet exciton fission, introduced in the previous paper [T. C. Berkelbach, M. S. Hybertsen, and D. R. Reichman, J. Chem. Phys. 138, 114102 (2013)] to molecular dimers of pentacene, a widely studied material that exhibits singlet fission in the crystal phase. We address a longstanding theoretical issue, namely whether singlet fission proceeds via two sequential electron transfer steps mediated by charge-transfer states or via a direct two-electron transfer process. We find evidence for a superexchange mediated mechanism, whereby the fission process proceeds through virtual charge-transfer states which may be very high in energy. In particular, this mechanism predicts efficient singlet fission on the sub-picosecond timescale, in reasonable agreement with experiment. We investigate the role played by molecular vibrations in mediating relaxation and decoherence, finding that different physically reasonable forms for the bath relaxation function give similar results. We also examine the competing direct coupling mechanism and find it to yield fission rates slower in comparison with the superexchange mechanism for the dimer. We discuss implications for crystalline pentacene, including the limitations of the dimer model. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4794427]
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available