Citation

BibTex format

@article{Lubert-Perquel:2020:10.1021/acs.jpclett.0c02505,
author = {Lubert-Perquel, D and Szumska, AA and Azzouzi, M and Salvadori, E and Ruloff, S and Kay, CMW and Nelson, J and Heutz, S},
doi = {10.1021/acs.jpclett.0c02505},
journal = {Journal of Physical Chemistry Letters},
pages = {9557--9565},
title = {Structure dependence of kinetic and thermodynamic parameters in singlet fission processes.},
url = {http://dx.doi.org/10.1021/acs.jpclett.0c02505},
volume = {11},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Singlet fission-whereby one absorbed photon generates two coupled triplet excitons-is a key process for increasing the efficiency of optoelectronic devices by overcoming the Shockley-Queisser limit. A crucial parameter is the rate of dissociation of the coupled triplets, as this limits the number of free triplets subsequently available for harvesting and ultimately the overall efficiency of the device. Here we present an analysis of the thermodynamic and kinetic parameters for this process in parallel and herringbone dimers measured by electron paramagnetic resonance spectroscopy in coevaporated films of pentacene in p-terphenyl. The rate of dissociation is higher for parallel dimers than for their herringbone counterparts, as is the rate of recombination to the ground state. DFT calculations, which provide the magnitude of the electronic coupling as well as the distribution of molecular orbitals for each geometry, suggest that weaker triplet coupling in the parallel dimer is the driving force for faster dissociation. Conversely, localization of the molecular orbitals and a stronger triplet-triplet interaction result in slower dissociation and recombination. The identification and understanding of how the intermolecular geometry promotes efficient triplet dissociation provide the basis for control of triplet coupling and thereby the optimization of one important parameter of device performance.
AU  - Lubert-Perquel,D
AU  - Szumska,AA
AU  - Azzouzi,M
AU  - Salvadori,E
AU  - Ruloff,S
AU  - Kay,CMW
AU  - Nelson,J
AU  - Heutz,S
DO  - 10.1021/acs.jpclett.0c02505
EP  - 9565
PY  - 2020///
SN  - 1948-7185
SP  - 9557
TI  - Structure dependence of kinetic and thermodynamic parameters in singlet fission processes.
T2  - Journal of Physical Chemistry Letters
UR  - http://dx.doi.org/10.1021/acs.jpclett.0c02505
UR  - https://www.ncbi.nlm.nih.gov/pubmed/33119322
UR  - https://pubs.acs.org/doi/10.1021/acs.jpclett.0c02505
UR  - http://hdl.handle.net/10044/1/84758
VL  - 11
ER  -
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