Title: Excited-State Dynamics of 5,14- vs 6,13-Bis(trialkylsilylethynyl)-Substituted Pentacenes: Implications for Singlet Fission

Abstract

Singlet fission is a process in conjugated organic materials that has the potential to considerably improve the performance of devices in many applications, including solar energy conversion. In any application involving singlet fission, efficient triplet harvesting is essential. At present, not much is known about molecular packing arrangements detrimental to singlet fission. In this work, we report a molecular packing arrangement in crystalline films of 5,14-bis(triisopropylsilylethynyl)-substituted pentacene, specifically a local (pairwise) packing arrangement, responsible for complete quenching of triplet pairs generated via singlet fission. We first demonstrate that the energetic condition necessary for singlet fission is satisfied in amorphous films of the 5,14-substituted pentacene derivative. However, while triplet pairs form highly efficiently in the amorphous films, only a modest yield of independent triplets is observed. In crystalline films, triplet pairs also form highly efficiently, although independent triplets are not observed because triplet pairs decay rapidly and are quenched completely. We assign the quenching to a rapid nonadiabatic transition directly to the ground state. Detrimental quenching is observed in crystalline films of two additional 5,14-bis(trialkylsilylethynyl)-substituted pentacenes with either ethyl or isobutyl substituents. Developing a better understanding of the losses identified in this work, and associated molecular packing, may benefit overcoming lossesmore » in solids of other singlet fission materials.« less

Authors:

Pensack, Ryan D.  ^[1];

• Search DOE PAGES for author "Pensack, Ryan D."
• Search DOE PAGES for ORCID "0000-0002-1302-1770"

Purdum, Geoffrey E. ^[2]; Mazza, Samuel M. ^[3]; Grieco, Christopher  ^[4];

• Search DOE PAGES for author "Grieco, Christopher"
• Search DOE PAGES for ORCID "0000-0002-3741-7702"

Asbury, John B.  ^[4];

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• Search DOE PAGES for ORCID "0000-0002-3641-7276"

Anthony, John E.  ^[3];

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• Search DOE PAGES for ORCID "0000-0002-8972-1888"

Loo, Yueh-Lin  ^[5];

• Search DOE PAGES for author "Loo, Yueh-Lin"
• Search DOE PAGES for ORCID "0000-0002-4284-0847"

Scholes, Gregory D.  ^[1]

• Search DOE PAGES for author "Scholes, Gregory D."
• Search DOE PAGES for ORCID "0000-0003-3336-7960"

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+ Show Author Affiliations

1. Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
2. Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States
3. Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
4. Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
5. Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States, Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States

Publication Date:

Mon Jun 06 00:00:00 EDT 2022

Research Org.:

Boise State Univ., ID (United States); Princeton Univ., NJ (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; National Science Foundation (NSF)

OSTI Identifier:

1871272

Alternate Identifier(s):

OSTI ID: 1873107; OSTI ID: 1906356

Grant/Contract Number:  

SC0015429; SC0019349

Resource Type:

Published Article

Journal Name:

Journal of Physical Chemistry. C

Additional Journal Information:

Journal Name: Journal of Physical Chemistry. C Journal Volume: 126 Journal Issue: 23; Journal ID: ISSN 1932-7447

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Excitons; Light absorption; Molecules; Nuclear fission; Oligomers