Resonance Raman Characterization of Tetracene Monomer and Nanocrystals: Excited State Lattice Distortions With Implications For Efficient Singlet Fission
Abstract
The characterization of specific phonon modes and exciton states that lead to efficient singlet fission (SF) may be instrumental in the design of the next generation of high-efficiency photovoltaic devices. To this end, we analyze the absolute resonance Raman (RR) cross sections for tetracene (Tc) both as a monomer in solution and as a crystalline solid in an aqueous suspension of nanocrystals. For both systems, a time-dependent wavepacket model is developed that is consistent with the absolute RR cross sections, the magnitude of the absorption cross sections, and the vibronic line shapes of the fluorescence. In the monomer, the intramolecular reorganization energy is between 1500 and 1800 cm–1 and the solvent reorganization energy is 70 cm–1. In nanocrystals, the total reorganization is diminished to less than 600 cm–1. The lowest energy exciton has an estimated intramolecular reorganization energy between 300 and 500 cm–1 while intermolecular librational phonons have a reorganization energy of about 130 cm–1. The diminished reorganization energy of the nanocrystal is interpreted in the context of the delocalization of the band-edge exciton onto about ∼7 molecules. When electron and electron–hole correlations are included within many-body perturbation theory, the polarized absorption spectra of crystalline Tc are calculated and foundmore »
- Authors:
-
- Univ. of California, Berkeley, CA (United States). Dept. of Chemistry
- Univ. of California, Berkeley, CA (United States). Dept. of Physics
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1527354
- Grant/Contract Number:
- AC02-05CH11231
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory
- Additional Journal Information:
- Journal Volume: 123; Journal Issue: 17; Journal ID: ISSN 1089-5639
- Publisher:
- American Chemical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Citation Formats
Ellis, Scott R., Dietze, Daniel R., Rangel, Tonatiuh, Brown-Altvater, Florian, Neaton, Jeffrey B., and Mathies, Richard A. Resonance Raman Characterization of Tetracene Monomer and Nanocrystals: Excited State Lattice Distortions With Implications For Efficient Singlet Fission. United States: N. p., 2019.
Web. doi:10.1021/acs.jpca.9b02986.
Ellis, Scott R., Dietze, Daniel R., Rangel, Tonatiuh, Brown-Altvater, Florian, Neaton, Jeffrey B., & Mathies, Richard A. Resonance Raman Characterization of Tetracene Monomer and Nanocrystals: Excited State Lattice Distortions With Implications For Efficient Singlet Fission. United States. https://doi.org/10.1021/acs.jpca.9b02986
Ellis, Scott R., Dietze, Daniel R., Rangel, Tonatiuh, Brown-Altvater, Florian, Neaton, Jeffrey B., and Mathies, Richard A. Fri .
"Resonance Raman Characterization of Tetracene Monomer and Nanocrystals: Excited State Lattice Distortions With Implications For Efficient Singlet Fission". United States. https://doi.org/10.1021/acs.jpca.9b02986. https://www.osti.gov/servlets/purl/1527354.
@article{osti_1527354,
title = {Resonance Raman Characterization of Tetracene Monomer and Nanocrystals: Excited State Lattice Distortions With Implications For Efficient Singlet Fission},
author = {Ellis, Scott R. and Dietze, Daniel R. and Rangel, Tonatiuh and Brown-Altvater, Florian and Neaton, Jeffrey B. and Mathies, Richard A.},
abstractNote = {The characterization of specific phonon modes and exciton states that lead to efficient singlet fission (SF) may be instrumental in the design of the next generation of high-efficiency photovoltaic devices. To this end, we analyze the absolute resonance Raman (RR) cross sections for tetracene (Tc) both as a monomer in solution and as a crystalline solid in an aqueous suspension of nanocrystals. For both systems, a time-dependent wavepacket model is developed that is consistent with the absolute RR cross sections, the magnitude of the absorption cross sections, and the vibronic line shapes of the fluorescence. In the monomer, the intramolecular reorganization energy is between 1500 and 1800 cm–1 and the solvent reorganization energy is 70 cm–1. In nanocrystals, the total reorganization is diminished to less than 600 cm–1. The lowest energy exciton has an estimated intramolecular reorganization energy between 300 and 500 cm–1 while intermolecular librational phonons have a reorganization energy of about 130 cm–1. The diminished reorganization energy of the nanocrystal is interpreted in the context of the delocalization of the band-edge exciton onto about ∼7 molecules. When electron and electron–hole correlations are included within many-body perturbation theory, the polarized absorption spectra of crystalline Tc are calculated and found to be in agreement with experiment. The low-lying exciton states and optically active phonons that contribute to the polarized crystal absorption are identified. The likely role of coherent exciton phonon evolution in the SF process is discussed.},
doi = {10.1021/acs.jpca.9b02986},
journal = {Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory},
number = 17,
volume = 123,
place = {United States},
year = {Fri Apr 05 00:00:00 EDT 2019},
month = {Fri Apr 05 00:00:00 EDT 2019}
}
Web of Science