1
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Eaves JD. Multielectron Dynamics in the Condensed Phase: Quantum Structure-Function Relationships. Annu Rev Phys Chem 2024; 75:437-456. [PMID: 38941526 DOI: 10.1146/annurev-physchem-042018-052515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2024]
Abstract
Quantum information promises dramatic advances in computing last seen in the digital revolution, but quantum hardware is fragile, noisy, and resource intensive. Chemistry has a role in developing new materials for quantum information that are robust to noise, scalable, and operable in ambient conditions. While molecular structure is the foundation for understanding mechanism and reactivity, molecular structure/quantum function relationships remain mostly undiscovered. Using singlet fission as a specific example of a multielectron process capable of producing long-lived spin-entangled electronic states at high temperatures, I describe how to exploit molecular structure and symmetry to gain quantum function and how some principles learned from singlet fission apply more broadly to quantum science.
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Affiliation(s)
- Joel D Eaves
- Department of Chemistry, University of Colorado, Boulder, Colorado, USA;
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2
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Lin LC, Dill RD, Thorley KJ, Parkin SR, Anthony JE, Johnson JC, Damrauer NH. Revealing the Singlet Fission Mechanism for a Silane-Bridged Thienotetracene Dimer. J Phys Chem A 2024; 128:3982-3992. [PMID: 38717589 PMCID: PMC11129308 DOI: 10.1021/acs.jpca.4c01463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 05/24/2024]
Abstract
Tetraceno[2,3-b]thiophene is regarded as a strong candidate for singlet fission-based solar cell applications due to its mixed characteristics of tetracene and pentacene that balance exothermicity and triplet energy. An electronically weakly coupled tetraceno[2,3-b]thiophene dimer (Et2Si(TIPSTT)2) with a single silicon atom bridge has been synthesized, providing a new platform to investigate the singlet fission mechanism involving the two acene chromophores. We study the excited state dynamics of Et2Si(TIPSTT)2 by monitoring the evolution of multiexciton coupled triplet states, 1TT to 5TT to 3TT to T1 + S0, upon photoexcitation with transient absorption, temperature-dependent transient absorption, and transient/pulsed electron paramagnetic resonance spectroscopies. We find that the photoexcited singlet lifetime is 107 ps, with 90% evolving to form the TT state, and the complicated evolution between the multiexciton states is unraveled, which can be an important reference for future efforts toward tetraceno[2,3-b]thiophene-based singlet fission solar cells.
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Affiliation(s)
- Liang-Chun Lin
- Department
of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Ryan D. Dill
- Department
of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Karl J. Thorley
- Department
of Chemistry & Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506-0055, United States
| | - Sean R. Parkin
- Department
of Chemistry & Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506-0055, United States
| | - John E. Anthony
- Department
of Chemistry & Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky 40506-0055, United States
| | - Justin C. Johnson
- National
Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Niels H. Damrauer
- Department
of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Renewable
and Sustainable Energy Institute (RASEI), University of Colorado Boulder, Boulder, Colorado 80309, United States
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3
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Kim J, Teo HT, Hong Y, Cha H, Kim W, Chi C, Kim D. Elucidating Singlet-Fission-Born Multiexciton Dynamics via Molecular Engineering: A Dilution Principle Extended to Quintet Triplet Pair. J Am Chem Soc 2024; 146:10833-10846. [PMID: 38578848 DOI: 10.1021/jacs.4c01326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
Multiexciton in singlet exciton fission represents a critical quantum state with significant implications for both solar cell applications and quantum information science. Two distinct fields of interest explore contrasting phenomena associated with the geminate triplet pair: one focusing on the persistence of long-lived correlation and the other emphasizing efficient decorrelation. Despite the pivotal nature of multiexciton processes, a comprehensive understanding of their dependence on the structural and spin properties of materials is currently lacking in experimental realizations. To address this gap in knowledge, molecular engineering was employed to modify the TIPS-tetracene structures, enabling an investigation of the structure-property relationships in spin-related multiexciton processes. In lieu of the time-resolved electron paramagnetic resonance technique, two time-resolved magneto-optical spectroscopies were implemented for quantitative analysis of spin-dependent multiexciton dynamics. The utilization of absorption and fluorescence signals as complementary optical readouts, in the presence of a magnetic field, provided crucial insights into geminate triplet pair dynamics. These insights encompassed the duration of multiexciton correlation and the involvement of the spin state in multiexciton decorrelation. Furthermore, simulations based on our kinetic models suggested a role for quintet dilution in multiexciton dynamics, surpassing the singlet dilution principle established by the Merrifield model. The integration of intricate model structures and time-resolved magneto-optical spectroscopies served to explicitly elucidate the interplay between structural and spin properties in multiexciton processes. This comprehensive approach not only contributes to the fundamental understanding of these processes but also aligns with and reinforces previous experimental studies of solid states and theoretical assessments.
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Affiliation(s)
- Juno Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hao Ting Teo
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Yongseok Hong
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hyojung Cha
- Department of Hydrogen and Renewable Energy, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Woojae Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Chunyan Chi
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
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4
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Majdecki M, Hsu CH, Wang CH, Shi EHC, Zakrocka M, Wei YC, Chen BH, Lu CH, Yang SD, Chou PT, Gaweł P. Singlet Fission in a New Series of Systematically Designed Through-space Coupled Tetracene Oligomers. Angew Chem Int Ed Engl 2024; 63:e202401103. [PMID: 38412017 DOI: 10.1002/anie.202401103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/14/2024] [Accepted: 02/24/2024] [Indexed: 02/28/2024]
Abstract
Singlet fission (SF) holds great promise for current photovoltaic technologies, where tetracenes, with their relatively high triplet energies, play a major role for application in silicon-based solar cells. However, the SF efficiencies in tetracene dimers are low due to the unfavorable energetics of their singlet and triplet energy levels. In the solid state, tetracene exhibits high yields of triplet formation through SF, raising great interest about the underlying mechanisms. To address this discrepancy, we designed and prepared a novel molecular system based on a hexaphenylbenzene core decorated with 2 to 6 tetracene chromophores. The spatial arrangement of tetracene units, induced by steric hindrance in the central part, dictates through-space coupling, making it a relevant model for solid-state chromophore organization. We then revealed a remarkable increase in SF quantum yield with the number of tetracenes, reaching quantitative (196 %) triplet pair formation in hexamer. We observed a short-lived correlated triplet pair and limited magnetic effects, indicating ineffective triplet dissociation in these through-space coupled systems. These findings emphasize the crucial role of the number of chromophores involved and the interchromophore arrangement for the SF efficiency. The insights gained from this study will aid designing more efficient and technology-compatible SF systems for applications in photovoltaics.
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Affiliation(s)
- Maciej Majdecki
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Chao-Hsien Hsu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Chih-Hsing Wang
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Emily Hsue-Chi Shi
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Magdalena Zakrocka
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
| | - Yu-Chen Wei
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Bo-Han Chen
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Chih-Hsuan Lu
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Shang-Da Yang
- Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan
| | - Przemysław Gaweł
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland
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5
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Pompetti N, Smyser KE, Feingold B, Owens R, Lama B, Sharma S, Damrauer NH, Johnson JC. Tetracene Diacid Aggregates for Directing Energy Flow toward Triplet Pairs. J Am Chem Soc 2024; 146. [PMID: 38606884 PMCID: PMC11046478 DOI: 10.1021/jacs.4c02058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/13/2024]
Abstract
A comprehensive investigation of the solution-phase photophysics of tetracene bis-carboxylic acid [5,12-tetracenepropiolic acid (Tc-DA)] and its related methyl ester [5,12-tetracenepropynoate (Tc-DE)], a non-hydrogen-bonding counterpart, reveals the role of the carboxylic acid moiety in driving molecular aggregation and concomitant excited-state behavior. Low-concentration solutions of Tc-DA exhibit similar properties to the popular 5,12-bis((triisopropylsilyl)ethynl)tetracene, but as the concentration increases, evidence for aggregates that form excimers and a new mixed-state species with charge-transfer (CT) and correlated triplet pair (TT) character is revealed by transient absorption and fluorescence experiments. Aggregates of Tc-DA evolve further with concentration toward an additional phase that is dominated by the mixed CT/TT state which is the only state present in Tc-DE aggregates and can be modulated with the solvent polarity. Computational modeling finds that cofacial arrangement of Tc-DA and Tc-DE subunits is the most stable aggregate structure and this agrees with results from 1H NMR spectroscopy. The calculated spectra of these cofacial dimers replicate the observed broadening in ground-state absorption as well as accurately predict the formation of a near-UV transition associated with a CT between molecular subunits that is unique to the specific aggregate structure. Taken together, the results suggest that the hydrogen bonding between Tc-DA molecules and the associated disruption of hydrogen bonding with solvent produce a regime of dimer-like behavior, absent in Tc-DE, that favors excimers rather than CT/TT mixed states. The control of aggregate size and structure using distinct functional groups, solute concentration, and solvent in tetracene promises new avenues for its use in light-harvesting schemes.
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Affiliation(s)
- Nicholas
F. Pompetti
- National
Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, United States
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Kori E. Smyser
- University
of Colorado, Boulder, Colorado 80401, United States
| | | | - Raythe Owens
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Bimala Lama
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Sandeep Sharma
- University
of Colorado, Boulder, Colorado 80401, United States
| | - Niels H. Damrauer
- University
of Colorado, Boulder, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, University
of Colorado Boulder, Boulder, Colorado 80401, United States
| | - Justin C. Johnson
- National
Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, University
of Colorado Boulder, Boulder, Colorado 80401, United States
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6
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Hayasaka R, Sakai H, Fuki M, Okamoto T, Khan R, Higashi M, Tkachenko NV, Kobori Y, Hasobe T. The Effect of Torsional Motion on Multiexciton Formation through Intramolecular Singlet Fission in Ferrocene-Bridged Pentacene Dimers. Angew Chem Int Ed Engl 2024; 63:e202315747. [PMID: 38179830 DOI: 10.1002/anie.202315747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/30/2023] [Accepted: 01/04/2024] [Indexed: 01/06/2024]
Abstract
A series of ferrocene(Fc)-bridged pentacene(Pc)-dimers [Fc-Ph(2,n)-(Pc)2 : n=number of phenylene spacers] were synthesized to examine the tortional motion effect of Fc-terminated phenylene linkers on strongly coupled quintet multiexciton (5 TT) formation through intramolecular singlet fission (ISF). Fc-Ph(2,4)-(Pc)2 has a relatively small electronic coupling and large conformational flexibility according to spectroscopic and theoretical analyses. Fc-Ph(2,4)-(Pc)2 exhibits a high-yield 5 TT together with quantitative singlet TT (1 TT) generation through ISF. This demonstrates a much more efficient ISF than those of other less flexible Pc dimers. The activation entropy in 1 TT spin conversion of Fc-Ph(2,4)-(Pc)2 is larger than those of the other systems due to the larger conformational flexibility associated with the torsional motion of the linkers. The torsional motion of linkers in 1 TT is attributable to weakened metal-ligand bonding in the Fc due to hybridization of the hole level of Pc to Fc in 1 TT unpaired orbitals.
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Affiliation(s)
- Ryo Hayasaka
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Masaaki Fuki
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- CREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Tsubasa Okamoto
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- CREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Ramsha Khan
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Masahiro Higashi
- Department of Complex Systems Science, Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- CREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
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7
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Gilligan AT, Owens R, Miller EG, Pompetti NF, Damrauer NH. Enhancing NIR-to-visible upconversion in a rigidly coupled tetracene dimer: approaching statistical limits for triplet-triplet annihilation using intramolecular multiexciton states. Chem Sci 2024; 15:1283-1296. [PMID: 38274080 PMCID: PMC10806848 DOI: 10.1039/d3sc04795d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 12/11/2023] [Indexed: 01/27/2024] Open
Abstract
Important applications of photon upconversion through triplet-triplet annihilation require conversion of near-IR photons to visible light. Generally, however, efficiencies in this spectral region lag behind bluer analogues. Herein we consider potential benefits from a conformationally well-defined covalent dimer annihilator TIPS-BTX in studies that systematically compare function to a related monomer model TIPS-tetracene (TIPS-Tc). TIPS-BTX exhibits weak electronic coupling between chromophores juxtaposed about a polycyclic bridge. We report an upconversion yield ϕUC for TIPS-BTX that is more than 20× larger than TIPS-Tc under comparable conditions (0.16%). While the dimer ϕUC is low compared to bluer champion systems, this yield is amongst the largest so-far reported for a tetracenic dimer system and is achieved under unoptimized conditions suggesting a significantly higher ceiling. Further investigation shows the ϕUC enhancement for the dimer is due exclusively to the TTA process with an effective yield more that 30× larger for TIPS-BTX compared to TIPS-Tc. The ϕTTA enhancement for TIPS-BTX relative to TIPS-Tc is indicative of participation by intramolecular multiexciton states with evidence presented in spin statistical arguments that the 5TT is involved in productive channels. For TIPS-BTX we report a spin-statistical factor f = 0.42 that matches or exceeds values found in champion annihilator systems such as DPA. At the same time, the poor relative efficiency of TIPS-Tc suggests involvement of non-productive bimolecular channels and excimeric states are suspected. Broadly these studies indicate that funneling of photogenerated electronic states into productive pathways, and avoiding parasitic ones, remains central to the development of champion upconversion systems.
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Affiliation(s)
- Alexander T Gilligan
- Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Raythe Owens
- Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Ethan G Miller
- Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Nicholas F Pompetti
- Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Niels H Damrauer
- Department of Chemistry, University of Colorado Boulder Boulder Colorado 80309 USA
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder Boulder Colorado 80309 USA
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8
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Reid OG, Johnson JC, Eaves JD, Damrauer NH, Anthony JE. Molecular Control of Triplet-Pair Spin Polarization and Its Optoelectronic Magnetic Resonance Probes. Acc Chem Res 2024; 57:59-69. [PMID: 38103045 PMCID: PMC10765369 DOI: 10.1021/acs.accounts.3c00556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 12/17/2023]
Abstract
ConspectusPreparing and manipulating pure magnetic states in molecular systems are the key initial requirements for harnessing the power of synthetic chemistry to drive practical quantum sensing and computing technologies. One route for achieving the requisite higher spin states in organic systems exploits the phenomenon of singlet fission, which produces pairs of triplet excited states from initially photoexcited singlets in molecular assemblies with multiple chromophores. The resulting spin states are characterized by total spin (quintet, triplet, or singlet) and its projection onto a specified molecular or magnetic field axis. These excited states are typically highly polarized but exhibit an impure spin population pattern. Herein, we report the prediction and experimental verification of molecular design rules that drive the population of a single pure magnetic state and describe the progress toward its experimental realization.A vital feature of this work is the close partnership among theory, chemical synthesis, and spectroscopy. We begin by presenting our theoretical framework for understanding spin manifold interconversion in singlet fission systems. This theory makes specific testable predictions about the intermolecular structure and orientation relative to an external magnetic field that should lead to pure magnetic state preparation and provides a powerful tool for interpreting magnetic spectra. We then test these predictions through detailed magnetic spectroscopy experiments on a series of new molecular architectures that meet one or more of the identified structural criteria. Many of these architectures rely on the synthesis of molecules with features unique to this effort: rigid bridges between chromophores in dimers, heteroacenes with tailored singlet/triplet-pair energy level matching, or side-group engineering to produce specific crystal structures. The spin evolution of these systems is revealed through our application and development of several magnetic resonance methods, each of which has different sensitivities and relevance in environments relevant to quantum applications.Our theoretical predictions prove to be remarkably consistent with our experimental results, though experimentally meeting all the structural prescriptions demanded by theory for true pure-state preparation remains a challenge. Our magnetic spectra agree with our model of triplet-pair behavior, including funneling of the population to the ms = 0 magnetic sublevel of the quintet under specified conditions in dimers and crystals, showing that this phenomenon is subject to control through molecular design. Moreover, our demonstration of novel and/or highly sensitive detection mechanisms of spin states in singlet fission systems, including photoluminescence (PL), photoinduced absorption (PA), and magnetoconductance (MC), points the way toward both a deeper understanding of how these systems evolve and technologically feasible routes toward experiments at the single-molecule quantum limit that are desirable for computational applications.
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Affiliation(s)
- Obadiah G. Reid
- National
Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, Boulder, Colorado 80309, United States
| | - Justin C. Johnson
- National
Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, Colorado 80401, United States
- Renewable
and Sustainable Energy Institute, Boulder, Colorado 80309, United States
| | - Joel D. Eaves
- Renewable
and Sustainable Energy Institute, Boulder, Colorado 80309, United States
- Department
of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Niels H. Damrauer
- Renewable
and Sustainable Energy Institute, Boulder, Colorado 80309, United States
- Department
of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - John E. Anthony
- Department
of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
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9
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Purdy M, Budden P, Fallon K, Gannett CN, Abruña HD, Zeng W, Friend R, Musser AJ, Bronstein H. Re-Thinking Dimer Design Principles with Indolonaphthyridine Intramolecular Singlet Fission. Chemistry 2023; 29:e202301547. [PMID: 37377132 DOI: 10.1002/chem.202301547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/27/2023] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Singlet fission is a phenomenon that could significantly improve the efficiency of photovoltaic devices. Indolonaphthyridine thiophene (INDT) is a photostable singlet fission material that could potentially be utilised in singlet fission-based photovoltaic devices. This study investigates the intramolecular singlet fission (i-SF) mechanism of INDT dimers linked via para-phenyl, meta-phenyl and fluorene bridging groups. Using ultra-fast spectroscopy the highest rate of singlet fission is found in the para-phenyl linked dimer. Quantum calculations show the para-phenyl linker encourages enhanced monomer electronic coupling. Increased rates of singlet fission were also observed in the higher polarity o-dichlorobenzene, relative to toluene, indicating that charge-transfer states have a role in mediating the process. The mechanistic picture of polarisable singlet fission materials, such as INDT, extends beyond the traditional mechanistic landscape.
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Affiliation(s)
- Michael Purdy
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Peter Budden
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Kealan Fallon
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Cara N Gannett
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Héctor D Abruña
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Weixuan Zeng
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Richard Friend
- Department of Physics, University of Cambridge, Cavendish Laboratory, Cambridge, CB3 0HE, UK
| | - Andrew J Musser
- Department of Chemistry & Chemical Biology, Cornell University, Baker Lab, 122, E Ave, Ithaca, NY, USA
| | - Hugo Bronstein
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
- Baker Lab, 122, E Ave, Ithaca, NY, USA
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10
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Lin LC, Smith T, Ai Q, Rugg BK, Risko C, Anthony JE, Damrauer NH, Johnson JC. Multiexciton quintet state populations in a rigid pyrene-bridged parallel tetracene dimer. Chem Sci 2023; 14:11554-11565. [PMID: 37886089 PMCID: PMC10599476 DOI: 10.1039/d3sc03153e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/01/2023] [Indexed: 10/28/2023] Open
Abstract
The multiexciton quintet state, 5TT, generated as a singlet fission intermediate in pairs of molecular chromophores, is a promising candidate as a qubit or qudit in future quantum information science schemes. In this work, we synthesize a pyrene-bridged parallel tetracene dimer, TPT, with an optimized interchromophore coupling strength to prevent the dissociation of 5TT to two decorrelated triplet (T1) states, which would contaminate the spin-state mixture. Long-lived and strongly spin-polarized pure 5TT state population is observed via transient absorption spectroscopy and transient/pulsed electron paramagnetic resonance spectroscopy, and its lifetime is estimated to be >35 µs, with the dephasing time (T2) for the 5TT-based qubit measured to be 726 ns at 10 K. Direct relaxation from 1TT to the ground state does diminish the overall excited state population, but the exclusive 5TT population at large enough persistent density for pulsed echo determination of spin coherence time is consistent with recent theoretical models that predict such behavior for strict parallel chromophore alignment and large exchange coupling.
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Affiliation(s)
- Liang-Chun Lin
- Department of Chemistry, University of Colorado Boulder Boulder CO 80309 USA
| | - Tanner Smith
- Department of Chemistry & Center for Applied Energy Research, University of Kentucky Lexington Kentucky 40506-0055 USA
| | - Qianxiang Ai
- Department of Chemistry & Center for Applied Energy Research, University of Kentucky Lexington Kentucky 40506-0055 USA
| | - Brandon K Rugg
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Chad Risko
- Department of Chemistry & Center for Applied Energy Research, University of Kentucky Lexington Kentucky 40506-0055 USA
| | - John E Anthony
- Department of Chemistry & Center for Applied Energy Research, University of Kentucky Lexington Kentucky 40506-0055 USA
| | - Niels H Damrauer
- Department of Chemistry, University of Colorado Boulder Boulder CO 80309 USA
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder Boulder CO 80309 USA
| | - Justin C Johnson
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
- Renewable and Sustainable Energy Institute (RASEI), University of Colorado Boulder Boulder CO 80309 USA
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11
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Majumder K, Mukherjee S, Panjwani NA, Lee J, Bittl R, Kim W, Patil S, Musser AJ. Controlling Intramolecular Singlet Fission Dynamics via Torsional Modulation of Through-Bond versus Through-Space Couplings. J Am Chem Soc 2023; 145:20883-20896. [PMID: 37705333 DOI: 10.1021/jacs.3c06075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/15/2023]
Abstract
Covalent dimers, particularly pentacenes, are the dominant platform for developing a mechanistic understanding of intramolecular singlet fission (iSF). Numerous studies have demonstrated that a photoexcited singlet state in these structures can rapidly and efficiently undergo exciton multiplication to form a correlated pair of triplets within a single molecule, with potential applications from photovoltaics to quantum information science. One of the most significant barriers limiting such dimers is the fast recombination of the triplet pair, which prevents spatial separation and the formation of long-lived triplet states. There is an ever-growing need to develop general synthetic strategies to control the evolution of triplets following iSF and enhance their lifetime. Here, we rationally tune the dihedral angle and interchromophore separation between pairs of pentacenes in a systematic series of bridging units to facilitate triplet separation. Through a combination of transient optical and spin-resonance techniques, we demonstrate that torsion within the linker provides a simple synthetic handle to tune the fine balance between through-bond and through-space interchromophore couplings that steer iSF. We show that the full iSF pathway from femtosecond to microsecond timescales is tuned through the static coupling set by molecular design and structural fluctuations that can be biased through steric control. Our approach highlights a straightforward design principle to generate paramagnetic spin pair states with higher yields.
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Affiliation(s)
- Kanad Majumder
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Soham Mukherjee
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Naitik A Panjwani
- Berlin Joint EPR Lab, Fachbereich Physik, Freie Universität, Berlin, Berlin 14195, Berlin, Germany
| | - Jieun Lee
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Robert Bittl
- Berlin Joint EPR Lab, Fachbereich Physik, Freie Universität, Berlin, Berlin 14195, Berlin, Germany
| | - Woojae Kim
- Department of Chemistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Satish Patil
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
| | - Andrew J Musser
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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12
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Kim J, Teo HT, Hong Y, Liau YC, Yim D, Han Y, Oh J, Kim H, Chi C, Kim D. Leveraging Charge-Transfer Interactions in Through-Space-Coupled Pentacene Dendritic Oligomer for Singlet Exciton Fission. J Am Chem Soc 2023; 145:19812-19823. [PMID: 37656929 DOI: 10.1021/jacs.3c05660] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
Singlet exciton fission in organic chromophores has received much attention during the past decade. Inspired by numerous spectroscopic studies in the solid state, there have been vigorous efforts to study singlet exciton fission dynamics in covalently bonded oligomers, which aims to investigate underlying mechanisms of this intriguing process in simplified model systems. In terms of through-space orbital interactions, however, most of covalently bonded pentacene oligomers studied so far fall into weakly interacting systems since they manifest chain-like structures based on various (non)conjugated linkers. Therefore, it remains as a compelling question to answer how through-space interactions in the solid state intervene this photophysical process since it is hypersensitive to displacements and orientations between neighboring chromophores. Herein, as one of experimental studies to answer this question, we introduced a tight-packing dendritic structure whose mesityl-pentacene constituents are coupled via moderate through-space orbital interactions. Based on the comparison with a suitably controlled dendritic structure, which is in a weak coupling regime, important mechanistic viewpoints are tackled such as configurational mixings between singlet, charge-transfer, and triplet pair states and the role of chromophore multiplication. We underscore that our through-space-coupled dendritic oligomer in a quasi-intermediate coupling regime provides a hint on the interplay of multiconfigurational excited-states, which might have drawn complexity in singlet exciton fission kinetics throughout numerous solid-state morphologies.
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Affiliation(s)
- Juno Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Hao Ting Teo
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Yongseok Hong
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
| | - Yuan Cheng Liau
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Daniel Yim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Yi Han
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Juwon Oh
- Department of ICT Environmental Health System and Department of Chemistry, Soonchunhyang University, Asan 31538, Korea
| | - Hyungjun Kim
- Department of Chemistry, Incheon National University, Incheon 22012, Korea
| | - Chunyan Chi
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Korea
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13
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Miller EG, Singh M, Parkin S, Sammakia T, Damrauer NH. Preparation of a Rigid and Nearly Coplanar Bis-tetracene Dimer through an Application of the CANAL Reaction. J Org Chem 2023; 88:12251-12256. [PMID: 37607040 DOI: 10.1021/acs.joc.3c00809] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
A rigid tetracene dimer with a substantial interchromophore distance has been prepared through an application of the recently developed catalytic arene-norbornene annulation (CANAL) reaction. An iterative cycloaddition route was found to be unsuccessful, so a shorter route was adopted whereby fragments were coupled in the penultimate step to form a 13:1 mixture of two diastereomers, the major of which was isolated and crystallized. Constituent tetracene moieties are linked with a rigid, well-defined bridge and feature a near-co-planar mutual orientation of the acenes.
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Affiliation(s)
- Ethan G Miller
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Madhu Singh
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Sean Parkin
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Tarek Sammakia
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Niels H Damrauer
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States
- Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, Colorado 80309, United States
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14
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Kefer O, Ahrens L, Han J, Wollscheid N, Misselwitz E, Rominger F, Freudenberg J, Dreuw A, Bunz UHF, Buckup T. Efficient Intramolecular Singlet Fission in Spiro-Linked Heterodimers. J Am Chem Soc 2023; 145:17965-17974. [PMID: 37535495 DOI: 10.1021/jacs.3c05518] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
We investigate intramolecular singlet fission (iSF) of spiro-linked azaacene heterodimers by time-resolved spectroscopy and quantum chemical calculations. Combining two different azaacenes through a nonconjugated linker using condensation chemistry furnishes azaacene heterodimers. Compared to their homodimers, iSF quantum yields are improved at an extended absorption range. The driving force of iSF, the energy difference ΔEiSF between the S1 state and the correlated triplet pair 1(TT), is tuned by the nature of the heterodimers. iSF is exothermic in all of the herein studied molecules. The overall quantum yield for triplet exciton formation reaches approximately 174%. This novel concept exploits large energy differences between singlet electronic states in combination with spatially fixed chromophores, which achieves efficient heterogeneous iSF, if the through-space interaction between the chromophores is minimal.
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Affiliation(s)
- Oskar Kefer
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Lukas Ahrens
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jie Han
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Nikolaus Wollscheid
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Erik Misselwitz
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jan Freudenberg
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Andreas Dreuw
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Uwe H F Bunz
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Tiago Buckup
- Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Ruprecht-Karls-Universität Heidelberg, D-69120 Heidelberg, Germany
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15
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Jung S, Wang L, Sugiyama H, Uekusa H, Katayama T, Kamada K, Hamura T, Tamai N. Intramolecular Singlet Fission in Pentacene Oligomers via an Intermediate State. J Phys Chem B 2023; 127:4554-4561. [PMID: 37191388 DOI: 10.1021/acs.jpcb.3c00516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Intramolecular singlet fission (iSF) is an efficient strategy of multiexciton generation via a singlet exciton splitting into a correlated triplet pair in one organic molecule with more than two chromophores. Propeller-shaped iptycene-linked triisopropylsilyl(TIPS)-ethynyl functionalized pentacene oligomers (pent-monomer, pent-dimer, and pent-trimer) were synthesized, and the iSF dynamics of pent-dimer and -trimer were monitored by a visible-near-IR transient absorption (TA) spectroscopy. Quantum yields of the triplet pair, ∼80%, of both estimated by near-IR TA spectral analysis are in good agreement with the results of global analysis and triplet sensitization experiments. The iSF rate of pent-trimer is slightly faster than that of pent-dimer even with one more chromophore site. The unexpectedly weak difference indicates the existence of an intermediate process to realize iSF. The intermediate process might be determined by through-bond electronic coupling of the homoconjugation bridge in the pentacene oligomers. Our results suggest the importance of the rigid bridge to the fast iSF rate and the elongated lifetime of the correlated triplet pair in pentacene oligomers.
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Affiliation(s)
- Sunna Jung
- Department of Applied Chemistry for Environment, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Li Wang
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Haruki Sugiyama
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Megro-ku, 152-8551 Tokyo, Japan
| | - Hidehiro Uekusa
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Megro-ku, 152-8551 Tokyo, Japan
| | - Tetsuro Katayama
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Kenji Kamada
- IFMRI, National Institute of Advanced Industrial Science and Technology (AIST), 563-8577 Osaka, Japan
| | - Toshiyuki Hamura
- Department of Applied Chemistry for Environment, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
| | - Naoto Tamai
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 669-1330 Sanda, Japan
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16
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Gotfredsen H, Thiel D, Greißel PM, Chen L, Krug M, Papadopoulos I, Ferguson MJ, Nielsen MB, Torres T, Clark T, Guldi DM, Tykwinski RR. Sensitized Singlet Fission in Rigidly Linked Axial and Peripheral Pentacene-Subphthalocyanine Conjugates. J Am Chem Soc 2023; 145:9548-9563. [PMID: 37083447 DOI: 10.1021/jacs.2c13353] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
The goal of harnessing the theoretical potential of singlet fission (SF), a process in which one singlet excited state is split into two triplet excited states, has become a central challenge in solar energy research. Covalently linked dimers provide crucial models for understanding the role of chromophore arrangement and coupling in SF. Sensitizers can be integrated into these systems to expand the absorption bandwidth through which SF can be accessed. Here, we define the role of the sensitizer-chromophore geometry in a sensitized SF model system. To this end, two conjugates have been synthesized consisting of a pentacene dimer (SF motif) connected via a rigid alkynyl bridge to a subphthalocyanine (the sensitizer motif) in either an axial or a peripheral arrangement. Steady-state and time-resolved photophysical measurements are used to confirm that both conjugates operate as per design, displaying near unity energy transfer efficiencies and high triplet quantum yields from SF. Decisively, energy transfer between the subphthalocyanine and pentacene dimer occurs ca. 26 times faster in the peripheral conjugate, even though the two chromophores are ca. 3 Å farther apart than in the axial conjugate. Following a theoretical evaluation of the dipolar coupling, Vdip2, and the orientation factor, κ2, of both the axial (Vdip2 = 140 cm-2; κ2 = 0.08) and the peripheral (Vdip2 = 724 cm-2; κ2 = 1.46) arrangements, we establish that this rate acceleration is due to a more favorable (nearly co-planar) relative orientation of the transition dipole moments of the subphthalocyanine and pentacenes in the peripheral constellation.
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Affiliation(s)
- Henrik Gotfredsen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø 2100, Denmark
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford OX1 3TA, U.K
| | - Dominik Thiel
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Phillip M Greißel
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Lan Chen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| | - Marcel Krug
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka819-0395, Japan
| | - Michael J Ferguson
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| | - Mogens Brøndsted Nielsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen Ø 2100, Denmark
| | - Tomás Torres
- Department of Organic Chemistry and Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Cantoblanco, Madrid 28049, Spain
- IMDEA Nanociencia, C/Faraday 9, Cantoblanco, Madrid 28049, Spain
| | - Timothy Clark
- Department of Chemistry and Pharmacy and Computer-Chemie-Center (CCC), Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstraße 25, Erlangen 91052, Germany
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy and Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany
| | - Rik R Tykwinski
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
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17
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Ansteatt S, Uthe B, Mandal B, Gelfand RS, Dunietz BD, Pelton M, Ptaszek M. Engineering giant excitonic coupling in bioinspired, covalently bridged BODIPY dyads. Phys Chem Chem Phys 2023; 25:8013-8027. [PMID: 36876508 DOI: 10.1039/d2cp05621f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Strong excitonic coupling in photosynthetic systems is believed to enable efficient light absorption and quantitative charge separation, motivating the development of artificial multi-chromophore arrays with equally strong or even stronger excitonic coupling. However, large excitonic coupling strengths have typically been accompanied by fast non-radiative recombination, limiting the potential of the arrays for solar energy conversion as well as other applications such as fluorescent labeling. Here, we report giant excitonic coupling leading to broad optical absorption in bioinspired BODIPY dyads that have high photostability, excited-state lifetimes at the nanosecond scale, and fluorescence quantum yields of nearly 50%. Through the synthesis, spectroscopic characterization, and computational modeling of a series of dyads with different linking moieties, we show that the strongest coupling is obtained with diethynylmaleimide linkers, for which the coupling occurs through space between BODIPY units with small separations and slipped co-facial orientations. Other linkers allow for broad tuning of both the relative through-bond and through-space coupling contributions and the overall strength of interpigment coupling, with a tradeoff observed in general between the strength of the two coupling mechanisms. These findings open the door to the synthesis of molecular systems that function effectively as light-harvesting antennas and as electron donors or acceptors for solar energy conversion.
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Affiliation(s)
- Sara Ansteatt
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
| | - Brian Uthe
- Department of Physics, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
| | - Bikash Mandal
- Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242, USA.
| | - Rachel S Gelfand
- Department of Physics, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
| | - Barry D Dunietz
- Department of Chemistry and Biochemistry, Kent State University, Kent, OH 44242, USA.
| | - Matthew Pelton
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA. .,Department of Physics, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
| | - Marcin Ptaszek
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
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18
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Dill RD, Smyser KE, Rugg BK, Damrauer NH, Eaves JD. Entangled spin-polarized excitons from singlet fission in a rigid dimer. Nat Commun 2023; 14:1180. [PMID: 36859382 PMCID: PMC9977721 DOI: 10.1038/s41467-023-36529-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 01/31/2023] [Indexed: 03/03/2023] Open
Abstract
Singlet fission, a process that splits a singlet exciton into a biexciton, has promise in quantum information. We report time-resolved electron paramagnetic resonance measurements on a conformationally well-defined acene dimer molecule, TIPS-BP1', designed to exhibit strongly state-selective relaxation to specific magnetic spin sublevels. The resulting optically pumped spin polarization is a nearly pure initial state from the ensemble. The long-lived spin coherences modulate the signal intrinsically, allowing a measurement scheme that substantially removes noise and uncertainty in the magnetic resonance spectra. A nonadiabatic transition theory with a minimal number of spectroscopic parameters allows the quantitative assignment and interpretation of the spectra. In this work, we show that the rigid dimer TIPS-BP1' supports persistent spin coherences at temperatures far higher than those used in conventional superconducting quantum hardware.
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Affiliation(s)
- Ryan D. Dill
- grid.266190.a0000000096214564Department of Chemistry, University of Colorado Boulder, Boulder, CO 80309 USA
| | - Kori E. Smyser
- grid.266190.a0000000096214564Department of Chemistry, University of Colorado Boulder, Boulder, CO 80309 USA
| | - Brandon K. Rugg
- grid.419357.d0000 0001 2199 3636National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401 USA
| | - Niels H. Damrauer
- grid.266190.a0000000096214564Department of Chemistry, University of Colorado Boulder, Boulder, CO 80309 USA ,grid.266190.a0000000096214564Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO 80309 USA
| | - Joel D. Eaves
- grid.266190.a0000000096214564Department of Chemistry, University of Colorado Boulder, Boulder, CO 80309 USA ,grid.266190.a0000000096214564Renewable and Sustainable Energy Institute, University of Colorado Boulder, Boulder, CO 80309 USA
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19
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Nakamura S, Sakai H, Fuki M, Ooie R, Ishiwari F, Saeki A, Tkachenko NV, Kobori Y, Hasobe T. Thermodynamic Control of Intramolecular Singlet Fission and Exciton Transport in Linear Tetracene Oligomers. Angew Chem Int Ed Engl 2023; 62:e202217704. [PMID: 36578175 DOI: 10.1002/anie.202217704] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/26/2022] [Accepted: 12/28/2022] [Indexed: 12/30/2022]
Abstract
We newly synthesized a series of homo- and hetero-tetracene (Tc) oligomers to propose a molecular design strategy for the efficient exciton transport in linear oligomers by promoting correlated triplet pair (TT) dissociation and controlling sequential exciton trapping process of individual doubled triplet excitons (T+T) by intramolecular singlet fission. First, entropic gain effects on the number of Tc units are examined by comparing Tc-homo-oligomers [(Tc)n : n=2, 4, 6]. Then, a comparison of (Tc)n and Tc-hetero-oligomer [TcF3 -(Tc)4 -TcF3 ] reveals the vibronic coupling effect for entropic gain. Observed entropic effects on the T+T formation indicated that the exciton migration is rationalized by number of possible TT states increased both by increasing the number of Tc units and by the vibronic levels at the terminal TcF3 units. Finally, we successfully observed high-yield exciton trapping process (trapped triplet yield: ΦTrT =176 %).
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Affiliation(s)
- Shunta Nakamura
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Masaaki Fuki
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan.,Department of Chemistry, Graduate School of Science, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Rikuto Ooie
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Fumitaka Ishiwari
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Akinori Saeki
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, 33720, Tampere, Finland
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan.,Department of Chemistry, Graduate School of Science, Kobe University, 1-1, Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
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20
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Liu H, Wang X, Ma L, Wang W, Liu S, Zhou J, Su P, Liu Z, Li Z, Lin X, Chen Y, Li X. Effects of the Separation Distance between Two Triplet States Produced from Intramolecular Singlet Fission on the Two-Electron-Transfer Process. J Am Chem Soc 2022; 144:15509-15518. [PMID: 35930671 DOI: 10.1021/jacs.2c03550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To harvest two triplet excitons of singlet fission (SF) via a two-electron transfer efficiently, the revelation of the key factors that influence the two-electron-transfer process is necessary. Here, by using steady-state and transient absorption/fluorescence spectroscopy, we investigated the two-electron-transfer process from the two triplet excitons of intramolecular SF (iSF) in a series of tetracene oligomers (dimer, trimer, and tetramer) with 7,7,8,8-tetracyanoquinodimethane (TCNQ) as an electron acceptor in solution. Quantitative two-electron transfer could be conducted for the trimer and tetramer, and the rate for the tetramer is faster than that for the trimer. However, the maximum efficiency of the two-electron transfer in the dimer is relatively low (∼47%). The calculation result of the free energy change (ΔG) of the second-electron transfer for these three compounds (-0.024, -0.061, and -0.074 eV for the dimer, trimer, and tetramer, respectively) is consistent with the experimental observation. The much closer ΔG value to zero for the dimer should be responsible for its low efficiency of the two-electron transfer. Different ΔG values for these three oligomers are attributed to the different Coulomb repulsive energies between the two positive charges generated after the two-electron transfer that is caused by their various intertriplet distances. This result reveals for the first time the important effect of the Coulomb repulsive energy, which depends on the intertriplet distance, on the two-electron transfer process from the two triplet excitons of iSF.
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Affiliation(s)
| | | | | | | | | | | | | | - Zhaobin Liu
- Shandong Energy Group Co., Ltd., Jinan, Shandong 250014, People's Republic of China
| | - Zhi Li
- Shandong Energy Group Co., Ltd., Jinan, Shandong 250014, People's Republic of China
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21
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Roy A, Diers JR, Niedzwiedzki DM, Meares A, Yu Z, Bhagavathy GV, Satraitis A, Kirmaier C, Ptaszek M, Bocian DF, Holten D. Photophysical Properties and Electronic Structure of Hydroporphyrin Dyads Exhibiting Strong Through-Space and Through-Bond Electronic Interactions. J Phys Chem A 2022; 126:5107-5125. [PMID: 35901315 DOI: 10.1021/acs.jpca.2c03114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electronic interactions between tetrapyrroles are utilized in natural photosynthetic systems to tune the light-harvesting and energy-/charge-transfer processes in these assemblies. Such interactions also can be employed to tailor the electronic properties of tetrapyrrolic dyads and larger arrays for use in materials science and biomedical research. Here, we have utilized static and time-resolved optical spectroscopy to characterize the optical absorption and emission properties of a set of chlorin and bacteriochlorin dyads with varying degrees of through-bond (TB) and through-space (TS) interactions between the constituent macrocycles. The dyads consist of two chlorins or two bacteriochlorins joined by a linker that utilizes a triple-double-triple-bond (enediyne) motif in which the double-bond portion is an ester-substituted ethylene or o-phenylene unit. The photophysical studies are coupled with density functional theory (DFT) calculations to probe the ground-state molecular orbital (MO) characteristics of the dyads and time-dependent DFT calculations (TDDFT) to elucidate excited-state properties. The latter include electronic characteristics of the singlet excited-state manifold and the absorption transitions to these states from the electronic ground state. A comparison of the MO and calculated spectral properties of each dyad with the linker present versus disrupted (by eliminating the double-bond portion) gives insight into the relative contributions of TB versus TS interactions to the electronic properties of the dyads. The results show that the TB and TS contributions are additive (constructively interfere), which is not always the case for molecular dyads. Most of the dyads have shorter lifetimes of the lowest singlet excited state compared to the parent monomer, which derives from increased S1 → S0 internal conversion. The enhancement is greater for the dyads in benzonitrile than in toluene. The studies provide insights into the nature of the electronic interactions between the constituents in the tetrapyrrole arrays and how these interactions dictate the spectral properties and excited-state decay characteristics.
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Affiliation(s)
- Arpita Roy
- Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States
| | - James R Diers
- Department of Chemistry, University of California, Riverside, California 92521-0403, United States
| | - Dariusz M Niedzwiedzki
- Center for Solar Energy and Energy Storage, and Department of Energy, Environmental & Chemical Engineering, Washington University, St. Louis, Missouri 63130-4889, United States
| | - Adam Meares
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250-0001, United States
| | - Zhanqian Yu
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250-0001, United States
| | - Ganga Viswanathan Bhagavathy
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250-0001, United States
| | - Andrius Satraitis
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250-0001, United States
| | - Christine Kirmaier
- Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States
| | - Marcin Ptaszek
- Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250-0001, United States
| | - David F Bocian
- Department of Chemistry, University of California, Riverside, California 92521-0403, United States
| | - Dewey Holten
- Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States
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22
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Fan S, Li W, Li T, Gao F, Hu W, Liu S, Wang X, Liu H, Liu Z, Li Z, Chen Y, Li X. Singlet fission in colloid nanoparticles of amphipathic 9,10-bis(phenylethynyl)anthracene derivatives. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.113826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Duan Y, Zhang G, Liu X, Shi F, Wang T, Yan H, Xu H, Zhang L. Acene-Extended Triptycenes: Synthesis, Characterization, and Singlet Exciton Fission Properties. J Org Chem 2022; 87:8841-8848. [PMID: 35290059 DOI: 10.1021/acs.joc.1c02693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Three acene-extended triptycenes, TIPS-Antrip, TIPS-Tetrip, and TIPS-Pentrip, which contain TIPS-ethynyl functionalized anthracene, tetracene, and pentacene as subunits, respectively, are synthesized and characterized. It is found that the optoelectronic properties and crystal packing motifs could be modulated by changing the subunits. A preliminary exploration of the excited-state behavior of these molecules indicates that TIPS-Tetrip and TIPS-Pentrip exhibit intramolecular singlet fission (iSF).
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Affiliation(s)
- Yuxiao Duan
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Guowei Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Xinyue Liu
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Fenghui Shi
- AVIC Manufacturing Technology Institute Composite Technology Center, Beijing 101300, P. R. China
| | - Tingting Wang
- AVIC Manufacturing Technology Institute Composite Technology Center, Beijing 101300, P. R. China
| | - Hongchen Yan
- AVIC Manufacturing Technology Institute Composite Technology Center, Beijing 101300, P. R. China
| | - Hu Xu
- AVIC Manufacturing Technology Institute Composite Technology Center, Beijing 101300, P. R. China
| | - Lei Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
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24
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Lewis SG, Smyser KE, Eaves JD. Clock transitions guard against spin decoherence in singlet fission. J Chem Phys 2021; 155:194109. [PMID: 34800954 DOI: 10.1063/5.0069344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Short coherence times present a primary obstacle in quantum computing and sensing applications. In atomic systems, clock transitions (CTs), formed from avoided crossings in an applied Zeeman field, can substantially increase coherence times. We show how CTs can dampen intrinsic and extrinsic sources of quantum noise in molecules. Conical intersections between two periodic potentials form CTs in electron paramagnetic resonance experiments of the spin-polarized singlet fission photoproduct. We report on a pair of CTs for a two-chromophore molecule in terms of the Zeeman field strength, molecular orientation relative to the field, and molecular geometry.
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Affiliation(s)
- Sina G Lewis
- Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - Kori E Smyser
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - Joel D Eaves
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
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25
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Nakamura S, Sakai H, Fuki M, Kobori Y, Tkachenko NV, Hasobe T. Enthalpy-Entropy Compensation Effect for Triplet Pair Dissociation of Intramolecular Singlet Fission in Phenylene Spacer-Bridged Hexacene Dimers. J Phys Chem Lett 2021; 12:6457-6463. [PMID: 34236876 DOI: 10.1021/acs.jpclett.1c01430] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Hexacene (Hc) is highly promising for singlet fission (SF). However, the number of SFs in Hc is extremely limited. As far as Hc dimers in solution are concerned, there is no report on the observation of the dissociation process from a correlated triplet pair (TT) to an individual one. The emphasis in this study is on the first observation of the quantitative TT generation together with the orientation-dependent photophysical discussions for TT dissociation using para- and meta-phenyl-bridged Hc dimers. Moreover, the activation enthalpies of Hc dimers in TT dissociation are smaller than those of pentacene (Pc) dimers, whereas the relative entropic contributions for Gibbs free energy of activation are much larger than the enthalpic ones in both Hc and Pc dimers. This implies that the vibrational motions are responsible for the intramolecular conformation changes associated with the TT dissociation. Consequently, "enthalpy-entropy compensation" has a large impact on the rate constants and quantum yields.
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Affiliation(s)
- Shunta Nakamura
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
| | - Masaaki Fuki
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Yasuhiro Kobori
- Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
- Department of Chemistry, Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Nikolai V Tkachenko
- Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, 33101 Tampere, Finland
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan
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26
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Karlsson JKG, Atahan A, Harriman A, Tkachenko NV, Ward AD, Schaberle FA, Serpa C, Arnaut LG. Singlet Exciton Fission and Associated Enthalpy Changes with a Covalently Linked Bichromophore Comprising TIPS-Pentacenes Held in an Open Conformation. J Phys Chem A 2021; 125:1184-1197. [DOI: 10.1021/acs.jpca.0c09961] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joshua K. G. Karlsson
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Alparslan Atahan
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Anthony Harriman
- Molecular Photonics Laboratory, School of Natural and Environmental Sciences, Newcastle University, Bedson Building, Newcastle upon Tyne NE1 7RU, U.K
| | - Nikolai V. Tkachenko
- Faculty of Engineering and Natural Sciences, Tampere University, Koereakoulunkatu 7, FIN-33720 Tampere, Finland
| | - Andrew D. Ward
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Didcot OX11 0FA, U.K
| | - Fabio A. Schaberle
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Carlos Serpa
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Luis G. Arnaut
- CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
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27
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Abstract
Singlet fission (SF) is a photophysical downconversion pathway, in which a singlet excitation transforms into two triplet excited states. As such, it constitutes an exciton multiplication generation process, which is currently at the focal point for future integration into solar energy conversion devices. Beyond this, various other exciting applications were proposed, including quantum cryptography or organic light emitting diodes. Also, the mechanistic understanding evolved rapidly during the last year. Unfortunately, the number of suitable SF-chromophores is still limited. This is per se problematic, considering the wide range of envisaged applicability. With that in mind, we emphasize uncommon SF-scaffolds and outline requirements as well as strategies to expand the chromophore pool of SF-materials.
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Affiliation(s)
- Tobias Ullrich
- Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Department für Chemie und Pharmazie, Egerlandstr. 1-3, 91058 Erlangen, Germany.
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28
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Yoshino K, Sakai H, Shoji Y, Kajitani T, Anetai H, Akutagawa T, Fukushima T, Tkachenko NV, Hasobe T. Room-Temperature Pentacene Fluids: Oligoethylene Glycol Substituent-Controlled Morphologies and Singlet Fission. J Phys Chem B 2020; 124:11910-11918. [PMID: 33336576 DOI: 10.1021/acs.jpcb.0c09754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report the first synthesis of solvent-free pentacene fluids at room temperature together with observation of singlet fission (SF). Three pentacenes with different number of ethylene glycol (EG) side chains (n) were employed (denoted as (EG)n-Pc-(EG)n: n = 2, 3, and 4). The morphologies of these pentacenes largely depend on the lengths of EG chains (n). (EG)3-Pc-(EG)3 and (EG)4-Pc-(EG)4 indicate fluid compounds at room temperature, whereas (EG)2-Pc-(EG)2 is a solid compound. Microscopic clustering with short-range interactions between pentacene chromophores was confirmed in X-ray diffraction profiles of solvent-free fluids. Such a structural trend is an important origin of SF and consistent with the steady-state spectroscopic results. To one's surprise, femtosecond transient absorption spectroscopy demonstrated that SF occurred in thin films prepared from solvent-free fluids of (EG)3-Pc-(EG)3 and (EG)4-Pc-(EG)4 in spite of such excessive EG chains.
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Affiliation(s)
- Keisuke Yoshino
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| | - Hayato Sakai
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| | - Yoshiaki Shoji
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.,RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Takashi Kajitani
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.,Materials Analysis Division, Open Facility Center, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Hayato Anetai
- Graduate School of Engineering, Tohoku University, Aoba-ku, Sendai 980-8578, Japan
| | - Tomoyuki Akutagawa
- Graduate School of Engineering, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.,Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Takanori Fukushima
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
| | - Nikolai V Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, Tampere FI33720, Finland
| | - Taku Hasobe
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
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29
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Cruz CD, Chronister EL, Bardeen CJ. Using temperature dependent fluorescence to evaluate singlet fission pathways in tetracene single crystals. J Chem Phys 2020; 153:234504. [PMID: 33353314 DOI: 10.1063/5.0031458] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The temperature-dependent fluorescence spectrum, decay rate, and spin quantum beats are examined in single tetracene crystals to gain insight into the mechanism of singlet fission. Over the temperature range of 250 K-500 K, the vibronic lineshape of the emission indicates that the singlet exciton becomes localized at 400 K. The fission process is insensitive to this localization and exhibits Arrhenius behavior with an activation energy of 550 ± 50 cm-1. The damping rate of the triplet pair spin quantum beats in the delayed fluorescence also exhibits an Arrhenius temperature dependence with an activation energy of 165 ± 70 cm-1. All the data for T > 250 K are consistent with direct production of a spatially separated 1(T⋯T) state via a thermally activated process, analogous to spontaneous parametric downconversion of photons. For temperatures in the range of 20 K-250 K, the singlet exciton continues to undergo a rapid decay on the order of 200 ps, leaving a red-shifted emission that decays on the order of 100 ns. At very long times (≈1 µs), a delayed fluorescence component corresponding to the original S1 state can still be resolved, unlike in polycrystalline films. A kinetic analysis shows that the redshifted emission seen at lower temperatures cannot be an intermediate in the triplet production. When considered in the context of other results, our data suggest that the production of triplets in tetracene for temperatures below 250 K is a complex process that is sensitive to the presence of structural defects.
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Affiliation(s)
- Chad D Cruz
- Department of Chemistry, University of California Riverside, Riverside, California 92521, USA
| | - Eric L Chronister
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Las Vegas, Nevada 89154, USA
| | - Christopher J Bardeen
- Department of Chemistry, University of California Riverside, Riverside, California 92521, USA
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30
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Zirzlmeier J, Lavarda G, Gotfredsen H, Papadopoulos I, Chen L, Clark T, Tykwinski RR, Torres T, Guldi DM. Modulating the dynamics of Förster resonance energy transfer and singlet fission by variable molecular spacers. NANOSCALE 2020; 12:23061-23068. [PMID: 33179680 DOI: 10.1039/d0nr06285e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In contrast to previous work, the synergy between panchromatic absorption and molecular singlet fission (SF) is exploited to optimize solar energy conversion through evaluation of the distance dependence of intramolecular Förster Resonance Energy Transfer (i-FRET) in a series of subphthalocyanines (SubPcs) linked to pentacene dimers (Pnc2s). To provide control over i-FRET, the molecular spacer rather than the energy donating SubPc is tailored in the corresponding SubPc-Pnc2 conjugates in terms of length (i.e., the number of aryl units) and flexibility (i.e., presence or absence of a CH2 group). AM1-CIS calculations support the experiments, which underline the importance of the molecular spacer to impact not only the i-FRET dynamics, but also the dynamics of intramolecular singlet fission (i-SF). For example, an additional phenyl group slows down both i-FRET and i-SF by a factor of ∼3.8 and ∼1.6, respectively, by a quinone-like conjugation pattern that affords a pentacene acceptor orbital that is fairly delocalized over both pentacenes and the bridging phenyl.
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Affiliation(s)
- Johannes Zirzlmeier
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058 Erlangen, Germany.
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31
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Kim J, Teo HT, Hong Y, Oh J, Kim H, Chi C, Kim D. Multiexcitonic Triplet Pair Generation in Oligoacene Dendrimers as Amorphous Solid‐State Miniatures. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Juno Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Hao Ting Teo
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Yongseok Hong
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Juwon Oh
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Hyungjun Kim
- Department of Chemistry Incheon National University 22012 Incheon Korea
| | - Chunyan Chi
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Dongho Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
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32
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Parenti KR, He G, Sanders SN, Pun AB, Kumarasamy E, Sfeir MY, Campos LM. Bridge Resonance Effects in Singlet Fission. J Phys Chem A 2020; 124:9392-9399. [PMID: 33138366 DOI: 10.1021/acs.jpca.0c08427] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A major benefit of intramolecular singlet fission (iSF) materials, in which through-bond interactions mediate triplet pair formation, is the ability to control the triplet formation dynamics through molecular engineering. One common design strategy is the use of molecular bridges to mediate interchromophore interactions, decreasing electronic coupling by increasing chromophore-chromophore separation. Here, we report how the judicious choice of aromatic bridges can enhance chromophore-chromophore electronic coupling. This molecular engineering strategy takes advantage of "bridge resonance", in which the frontier orbital energies are nearly degenerate with those of the covalently linked singlet fission chromophores, resulting in fast iSF even at large interchromophore separations. Using transient absorption spectroscopy, we investigate this bridge resonance effect in a series of pentacene and tetracene-bridged dimers, and we find that the rate of triplet formation is enhanced as the bridge orbitals approach resonance. This work highlights the important role of molecular connectivity in controlling the rate of iSF through chemical bonds and establishes critical design principles for future use of iSF materials in optoelectronic devices.
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Affiliation(s)
- Kaia R Parenti
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Guiying He
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, United States.,Photonics Initiative, Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| | - Samuel N Sanders
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Andrew B Pun
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Elango Kumarasamy
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Matthew Y Sfeir
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, United States.,Photonics Initiative, Advanced Science Research Center, City University of New York, New York, New York 10031, United States
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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33
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Smyser KE, Eaves JD. Singlet fission for quantum information and quantum computing: the parallel JDE model. Sci Rep 2020; 10:18480. [PMID: 33116218 PMCID: PMC7595132 DOI: 10.1038/s41598-020-75459-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/22/2020] [Indexed: 11/09/2022] Open
Abstract
Singlet fission is a photoconversion process that generates a doubly excited, maximally spin entangled pair state. This state has applications to quantum information and computing that are only beginning to be realized. In this article, we construct and analyze a spin-exciton hamiltonian to describe the dynamics of the two-triplet state. We find the selection rules that connect the doubly excited, spin-singlet state to the manifold of quintet states and comment on the mechanism and conditions for the transition into formally independent triplets. For adjacent dimers that are oriented and immobilized in an inert host, singlet fission can be strongly state-selective. We make predictions for electron paramagnetic resonance experiments and analyze experimental data from recent literature. Our results give conditions for which magnetic resonance pulses can drive transitions between optically polarized magnetic sublevels of the two-exciton states, making it possible to realize quantum gates at room temperature in these systems.
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Affiliation(s)
- Kori E Smyser
- Department of Chemistry, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - Joel D Eaves
- Department of Chemistry, University of Colorado Boulder, Boulder, CO, 80309, USA.
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34
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Alagna N, Lustres JLP, Roozbeh A, Han J, Hahn S, Berger FJ, Zaumseil J, Dreuw A, Bunz UHF, Buckup T. Ultrafast Singlet Fission in Rigid Azaarene Dimers with Negligible Orbital Overlap. J Phys Chem B 2020; 124:9163-9174. [DOI: 10.1021/acs.jpcb.0c07096] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Nicolò Alagna
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jose Luis Pérez Lustres
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Ashkan Roozbeh
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jie Han
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Sebastian Hahn
- Organisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Felix J. Berger
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Jana Zaumseil
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Andreas Dreuw
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Uwe H. F. Bunz
- Organisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
| | - Tiago Buckup
- Physikalisch Chemisches Institut, Universität Heidelberg, D-69120 Heidelberg, Germany
- Centre for Advanced Materials, Universität Heidelberg, D-69120 Heidelberg, Germany
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35
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Zhang G, Xue N, Gu W, Yang X, Lv A, Zheng Y, Zhang L. Regiocontrolled dimerization of asymmetric diazaheptacene derivatives toward X-shaped porous semiconductors. Chem Sci 2020; 11:11235-11243. [PMID: 34094364 PMCID: PMC8162510 DOI: 10.1039/d0sc03744c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Conformationally rigid X-shaped PAHs are attracting interest due to their self-assembly into unique networks and as models to study through-space exciton and charge delocalization in one single molecule. We report here the synthesis of X-shaped PAHs by dimerization of diazaheptacene diimides. The diimide groups are employed to effectively direct the self-assembly into antiparallel dimer aggregates, which assist the compounds to undergo a regiocontrolled [4 + 4] dimerization, leading to an X-shaped conformation bearing electron-poor and -rich subunits. The resulting PAHs are found to pack in 2D layers with large open channels and infinite π⋯π arrays. Furthermore, these highly crystalline porous materials serve as electron-transporting materials in OFETs due to the long-range π-stacked arrays in the layers. This work presents a potentially generalizable strategy, which may provide a unique class of porous semiconductors for organic devices, taking advantage of their open channels. The synthesis of conformationally rigid X-shaped PAHs by regiocontrolled cyclodimerization of diazaheptacene diimides is presented. The resulting porous materials exhibit enhanced semiconducting behaviors with large open channels.![]()
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Affiliation(s)
- Guowei Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Ning Xue
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Wen Gu
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science Shanghai 201620 P. R. China
| | - Xingzhou Yang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC) Chengdu 610054 P. R. China
| | - Aifeng Lv
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science Shanghai 201620 P. R. China
| | - Yonghao Zheng
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC) Chengdu 610054 P. R. China
| | - Lei Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology Beijing 100029 P. R. China
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36
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Kim J, Teo HT, Hong Y, Oh J, Kim H, Chi C, Kim D. Multiexcitonic Triplet Pair Generation in Oligoacene Dendrimers as Amorphous Solid‐State Miniatures. Angew Chem Int Ed Engl 2020; 59:20956-20964. [DOI: 10.1002/anie.202008533] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Juno Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Hao Ting Teo
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Yongseok Hong
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Juwon Oh
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Hyungjun Kim
- Department of Chemistry Incheon National University 22012 Incheon Korea
| | - Chunyan Chi
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Dongho Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
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37
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Pace NA, Rugg BK, Chang CH, Reid OG, Thorley KJ, Parkin S, Anthony JE, Johnson JC. Conversion between triplet pair states is controlled by molecular coupling in pentadithiophene thin films. Chem Sci 2020; 11:7226-7238. [PMID: 34123008 PMCID: PMC8159287 DOI: 10.1039/d0sc02497j] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 06/21/2020] [Indexed: 11/21/2022] Open
Abstract
In singlet fission (SF) the initially formed correlated triplet pair state, 1(TT), may evolve toward independent triplet excitons or higher spin states of the (TT) species. The latter result is often considered undesirable from a light harvesting perspective but may be attractive for quantum information sciences (QIS) applications, as the final exciton pair can be spin-entangled and magnetically active with relatively long room temperature decoherence times. In this study we use ultrafast transient absorption (TA) and time-resolved electron paramagnetic resonance (TR-EPR) spectroscopy to monitor SF and triplet pair evolution in a series of alkyl silyl-functionalized pentadithiophene (PDT) thin films designed with systematically varying pairwise and long-range molecular interactions between PDT chromophores. The lifetime of the (TT) species varies from 40 ns to 1.5 μs, the latter of which is associated with extremely weak intermolecular coupling, sharp optical spectroscopic features, and complex TR-EPR spectra that are composed of a mixture of triplet and quintet-like features. On the other hand, more tightly coupled films produce broader transient optical spectra but simpler TR-EPR spectra consistent with significant population in 5(TT)0. These distinctions are rationalized through the role of exciton diffusion and predictions of TT state mixing with low exchange coupling J versus pure spin substate population with larger J. The connection between population evolution using electronic and spin spectroscopies enables assignments that provide a more detailed picture of triplet pair evolution than previously presented and provides critical guidance for designing molecular QIS systems based on light-induced spin coherence.
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Affiliation(s)
- Natalie A Pace
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Brandon K Rugg
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Christopher H Chang
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
| | - Obadiah G Reid
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
- Renewable and Sustainable Energy Institute, University of Colorado Boulder Boulder Colorado 80309 USA
| | - Karl J Thorley
- Department of Chemistry, University of Kentucky Lexington KY 40506 USA
| | - Sean Parkin
- Department of Chemistry, University of Kentucky Lexington KY 40506 USA
| | - John E Anthony
- Department of Chemistry, University of Kentucky Lexington KY 40506 USA
| | - Justin C Johnson
- National Renewable Energy Laboratory 15013 Denver West Parkway Golden Colorado 80401 USA
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38
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Singlet Fission in Self-assembled Amphipathic Tetracene Nanoparticles: Probing the Role of Charge-transfer State. J Photochem Photobiol A Chem 2020. [DOI: 10.1016/j.jphotochem.2020.112597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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39
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Hong Y, Kim J, Kim W, Kaufmann C, Kim H, Würthner F, Kim D. Efficient Multiexciton State Generation in Charge-Transfer-Coupled Perylene Bisimide Dimers via Structural Control. J Am Chem Soc 2020; 142:7845-7857. [DOI: 10.1021/jacs.0c00870] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Yongseok Hong
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Juno Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Woojae Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Christina Kaufmann
- Universitat Würzburg, Institut für Organische Chemie & Center for Nanosystems Chemistry, Am Hubland, Würzburg 97074, Germany
| | - Hyungjun Kim
- Department of Chemistry, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Korea
- Research Institute of Basic Sciences, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Korea
| | - Frank Würthner
- Universitat Würzburg, Institut für Organische Chemie & Center for Nanosystems Chemistry, Am Hubland, Würzburg 97074, Germany
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
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40
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Spatial separation of triplet excitons drives endothermic singlet fission. Nat Chem 2020; 12:391-398. [PMID: 32123340 DOI: 10.1038/s41557-020-0422-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/14/2020] [Indexed: 11/08/2022]
Abstract
Molecules that undergo singlet fission, converting singlet excitons into pairs of triplet excitons, have potential as photovoltaic materials. The possible advantages of endothermic singlet fission (enhanced use of photon energy and larger triplet energies for coupling with common absorbers) motivated us to assess the role of exciton delocalization in the activation of this process. Here we report the synthesis of a series of linear perylene oligomers that undergo endothermic singlet fission and have endothermicities in the range 5-10 kBT at room temperature in solution. We study these compounds using transient spectroscopy and modelling to unravel the singlet and triplet dynamics. We show that the minimal number of coupled chromophores needed to undergo endothermic singlet fission is three, which provides sufficient statistical space for triplet excitons to separate and avoid annihilation-and a subsequent fast return to the singlet state. Our data additionally suggest that torsional motion of chromophores about the molecular axis following triplet-pair separation contributes to the increase in entropy, thus lengthening the triplet lifetime in longer oligomers.
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41
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Matsuda S, Oyama S, Kobori Y. Electron spin polarization generated by transport of singlet and quintet multiexcitons to spin-correlated triplet pairs during singlet fissions. Chem Sci 2020; 11:2934-2942. [PMID: 34122794 PMCID: PMC8157521 DOI: 10.1039/c9sc04949e] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Singlet fission (SF) is expected to exceed the Shockley–Queisser theoretical limit of efficiency of organic solar cells. Transport of spin-entanglement in the triplet–triplet pair state via one singlet exciton is a promising phenomenon for several energy conversion applications including quantum information science. However, direct observation of electron spin polarization by transport of entangled spin-states has not been presented. In this study, time-resolved electron paramagnetic resonance has been utilized to observe the transportation of singlet and quintet characters generating correlated triplet–triplet (T + T) exciton-pair states by probing the electron spin polarization (ESP) generated in thin films of 6,13-bis(triisopropylsilylethynyl)pentacene. We have clearly demonstrated that the ESP detected at the resonance field positions of individual triplet excitons is dependent on the morphology and on the detection delay time after laser flash to cause SF. ESP was clearly explained by quantum superposition of singlet–triplet–quintet wavefunctions via picosecond triplet-exciton dissociation as the electron spin polarization transfer from strongly exchange-coupled singlet and quintet TT states to weakly-coupled spin-correlated triplet pair states. Although the coherent superposition of spin eigenstates was not directly detected, the present interpretation of the spin correlation of the separated T + T exciton pair may pave new avenues not only for elucidating the vibronic role in the de-coupling between two excitons but also for scalable quantum information processing using quick T + T dissociation via one-photon excitation. Singlet fission (SF) is expected to exceed the Shockley–Queisser theoretical limit of efficiency of organic solar cells.![]()
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Affiliation(s)
- Saki Matsuda
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
| | - Shinya Oyama
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
| | - Yasuhiro Kobori
- Department of Chemistry, Graduate School of Science, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan .,Molecular Photoscience Research Center, Kobe University 1-1 Rokkodai-cho, Nada-ku Kobe 657-8501 Japan
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42
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Korovina NV, Pompetti NF, Johnson JC. Lessons from intramolecular singlet fission with covalently bound chromophores. J Chem Phys 2020; 152:040904. [PMID: 32007061 DOI: 10.1063/1.5135307] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Molecular dimers, oligomers, and polymers are versatile components in photophysical and optoelectronic architectures that could impact a variety of applications. We present a perspective on such systems in the field of singlet fission, which effectively multiplies excitons and produces a unique excited state species, the triplet pair. The choice of chromophore and the nature of the attachment between units, both geometrical and chemical, play a defining role in the dynamical scheme that evolves upon photoexcitation. Specific final outcomes (e.g., separated and uncorrelated triplet pairs) are being sought through rational design of covalently bound chromophore architectures built with guidance from recent fundamental studies that correlate structure with excited state population flow kinetics.
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Affiliation(s)
- Nadezhda V Korovina
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
| | - Nicholas F Pompetti
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
| | - Justin C Johnson
- National Renewable Energy Laboratory, 15013 Denver West Pkwy, Golden, Colorado 80401, USA
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43
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Mora‐Fuentes JP, Papadopoulos I, Thiel D, Álvarez‐Boto R, Cortizo‐Lacalle D, Clark T, Melle‐Franco M, Guldi DM, Mateo‐Alonso A. Singlet Fission in Pyrene‐Fused Azaacene Dimers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201911529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Juan P. Mora‐Fuentes
- POLYMAT University of the Basque Country UPV/EHU Avenida de Tolosa 72 20018 Donostia-San Sebastian Spain
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany
| | - Dominik Thiel
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany
| | - Roberto Álvarez‐Boto
- CICECO—Aveiro Institute of Materials Department of Chemistry University of Aveiro 3810-193 Aveiro Portugal
| | - Diego Cortizo‐Lacalle
- POLYMAT University of the Basque Country UPV/EHU Avenida de Tolosa 72 20018 Donostia-San Sebastian Spain
| | - Timothy Clark
- Computer-Chemistry Centre Department of Chemistry and Pharmacy Friedrich-Alexander-Universität Erlangen-Nürnberg Naegelsbachstr. 25 91052 Erlangen Germany
| | - Manuel Melle‐Franco
- CICECO—Aveiro Institute of Materials Department of Chemistry University of Aveiro 3810-193 Aveiro Portugal
| | - Dirk M. Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany
| | - Aurelio Mateo‐Alonso
- POLYMAT University of the Basque Country UPV/EHU Avenida de Tolosa 72 20018 Donostia-San Sebastian Spain
- Ikerbasque Basque Foundation for Science Bilbao Spain
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44
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Mora‐Fuentes JP, Papadopoulos I, Thiel D, Álvarez‐Boto R, Cortizo‐Lacalle D, Clark T, Melle‐Franco M, Guldi DM, Mateo‐Alonso A. Singlet Fission in Pyrene-Fused Azaacene Dimers. Angew Chem Int Ed Engl 2020; 59:1113-1117. [PMID: 31647593 PMCID: PMC7687256 DOI: 10.1002/anie.201911529] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Indexed: 02/02/2023]
Abstract
Singlet fission has emerged as a promising strategy to avoid the loss of extra energy through thermalization in solar cells. A family of dimers consisting of nitrogen-doped pyrene-fused acenes that undergo singlet fission with triplet quantum yields as high as 125 % are presented. They provide new perspectives for nitrogenated polycyclic aromatic hydrocarbons and for the design of new materials for singlet fission.
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Affiliation(s)
- Juan P. Mora‐Fuentes
- POLYMATUniversity of the Basque Country UPV/EHUAvenida de Tolosa 7220018Donostia-San SebastianSpain
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular MaterialsFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr. 391058ErlangenGermany
| | - Dominik Thiel
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular MaterialsFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr. 391058ErlangenGermany
| | - Roberto Álvarez‐Boto
- CICECO—Aveiro Institute of MaterialsDepartment of ChemistryUniversity of Aveiro3810-193AveiroPortugal
| | - Diego Cortizo‐Lacalle
- POLYMATUniversity of the Basque Country UPV/EHUAvenida de Tolosa 7220018Donostia-San SebastianSpain
| | - Timothy Clark
- Computer-Chemistry CentreDepartment of Chemistry and PharmacyFriedrich-Alexander-Universität Erlangen-NürnbergNaegelsbachstr. 2591052ErlangenGermany
| | - Manuel Melle‐Franco
- CICECO—Aveiro Institute of MaterialsDepartment of ChemistryUniversity of Aveiro3810-193AveiroPortugal
| | - Dirk M. Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular MaterialsFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr. 391058ErlangenGermany
| | - Aurelio Mateo‐Alonso
- POLYMATUniversity of the Basque Country UPV/EHUAvenida de Tolosa 7220018Donostia-San SebastianSpain
- IkerbasqueBasque Foundation for ScienceBilbaoSpain
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45
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Triplet–Triplet Annihilation-Photon Upconversion Employing an Adamantane-linked Diphenylanthracene Dyad Strategy. J Photochem Photobiol A Chem 2020. [DOI: 10.1016/j.jphotochem.2019.112107] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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46
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Imperiale CJ, Green PB, Miller EG, Damrauer NH, Wilson MWB. Triplet-Fusion Upconversion Using a Rigid Tetracene Homodimer. J Phys Chem Lett 2019; 10:7463-7469. [PMID: 31751145 DOI: 10.1021/acs.jpclett.9b03115] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We demonstrate that a structurally rigid, weakly coupled molecular dimer can replace traditional monomeric annihilators for triplet fusion upconversion (TUC) in solution by observing emitted photons (λ = 540 nm) from a norbornyl-bridged tetracene homodimer following excitation of a triplet sensitizer at λ = 730 nm. Intriguingly, steady-state spectroscopy, kinetic simulations, and Stern-Volmer quenching experiments show that the dimer exhibits qualitatively different photophysics than its parent monomer: it is less effective at diffusion-mediated triplet exciton transfer, but it fuses extracted triplets more efficiently. Our results support the development of composite triplet-fusion platforms that go beyond diffusion-mediated triplet extraction, ultimately circumventing the concentration dependence of solution-phase TUC.
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Affiliation(s)
| | - Philippe B Green
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S3H6 , Canada
| | - Ethan G Miller
- Department of Chemistry and Biochemistry , University of Colorado, Boulder , Boulder , Colorado 80302 , United States
| | - Niels H Damrauer
- Department of Chemistry and Biochemistry , University of Colorado, Boulder , Boulder , Colorado 80302 , United States
| | - Mark W B Wilson
- Department of Chemistry , University of Toronto , Toronto , Ontario M5S3H6 , Canada
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47
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Zaykov A, Felkel P, Buchanan EA, Jovanovic M, Havenith RWA, Kathir RK, Broer R, Havlas Z, Michl J. Singlet Fission Rate: Optimized Packing of a Molecular Pair. Ethylene as a Model. J Am Chem Soc 2019; 141:17729-17743. [PMID: 31509712 DOI: 10.1021/jacs.9b08173] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A procedure is described for unbiased identification of all π-electron chromophore pair geometry choices that locally maximize the rate of conversion of a singlet exciton into a singlet biexciton (triplet pair), using a simplified version of the diabatic frontier orbital model of singlet fission (SF). The resulting approximate optimal geometries provide insight and are expected to represent useful starting points for searches by more advanced methods. The general procedure is illustrated on a pair of ethylenes as the simplest model of a π-electron system, but it is applicable to pairs of much larger molecules, with dozens of non-hydrogen atoms, and not necessarily planar. We first examine the value of |TA|2, the square of the electronic matrix element for SF with initial excitation fully localized on partner A, on a grid of several billion geometries within the six-dimensional space of physically realizable possibilities. Several of the optimized pair geometries are somewhat unexpected, but all are found to follow the qualitative guidance proposed earlier. In the neighborhood of each local maximum of |TA|2, consideration of mixing with charge-transfer configurations and of excitonic interaction between partners A and B determines the SF energy balance and yields squared matrix elements |T*|2 and |T**|2 for the lower and upper excitonic states S* and S**, respectively. Assuming Boltzmann populations of these states, the geometry is further optimized to maximize k, the sum of the SF rates obtained from Marcus theory, and this reorders the suitable geometries substantially. At 87 pair geometries, the |T*|2 and |T**|2 values are compared with those obtained from high-level ab initio nonorthogonal configuration interaction calculations and found to follow the same trend. Finally, the biexciton binding energy at the optimized geometries is calculated. Altogether, 13 significant local maxima of SF rate for a pair of ethylenes are identified in the physically relevant part of space that avoids molecular interpenetration in the hard-sphere approximation. The three best geometries are twist-stacked, slip-stacked, and L-shaped. The maxima occur at the (five-dimensional) surfaces of seven six-dimensional "parent" regions of space centered at physically inaccessible geometries at which the calculated SF rate is very large but the two ethylenes interpenetrate. The results are displayed in interactive graphics. The computer code ("Simple") written for these calculations is flexible in that it permits a choice of performing the search for local maxima in six dimensions on |TA|2, |T*|2, or k. It is available as freeware at https://cloud.uochb.cas.cz/simple .
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Affiliation(s)
- Alexandr Zaykov
- Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , 16610 Prague 6, Czech Republic.,Department of Physical Chemistry , University of Chemistry and Technology , 16628 Prague 6, Czech Republic
| | - Petr Felkel
- Faculty of Electrical Engineering , Czech Technical University in Prague , 16627 Prague 6, Czech Republic
| | - Eric A Buchanan
- Department of Chemistry , University of Colorado , Boulder , Colorado 80309-0215 , United States
| | - Milena Jovanovic
- Department of Chemistry , University of Colorado , Boulder , Colorado 80309-0215 , United States
| | - Remco W A Havenith
- Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4, 9747 AG Groningen , The Netherlands.,Stratingh Institute for Chemistry , University of Groningen , Nijenborgh 4, 9747 AG Groningen , The Netherlands.,Department of Inorganic and Physical Chemistry , Ghent University , Krijgslaan 281 (S3) , B-9000 Gent , Belgium
| | - R K Kathir
- Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4, 9747 AG Groningen , The Netherlands
| | - Ria Broer
- Zernike Institute for Advanced Materials , University of Groningen , Nijenborgh 4, 9747 AG Groningen , The Netherlands
| | - Zdeněk Havlas
- Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , 16610 Prague 6, Czech Republic
| | - Josef Michl
- Institute of Organic Chemistry and Biochemistry , Czech Academy of Sciences , 16610 Prague 6, Czech Republic.,Department of Chemistry , University of Colorado , Boulder , Colorado 80309-0215 , United States
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48
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Grieco C, Doucette GS, Munson KT, Swartzfager JR, Munro JM, Anthony JE, Dabo I, Asbury JB. Vibrational probe of the origin of singlet exciton fission in TIPS-pentacene solutions. J Chem Phys 2019; 151:154701. [DOI: 10.1063/1.5116586] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Christopher Grieco
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Grayson S. Doucette
- Intercollege Materials Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Kyle T. Munson
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John R. Swartzfager
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Jason M. Munro
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John E. Anthony
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, USA
| | - Ismaila Dabo
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - John B. Asbury
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
- Intercollege Materials Science and Engineering Program, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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49
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Tykwinski RR. Synthesis of Unsymmetrical Derivatives of Pentacene for Materials Applications. Acc Chem Res 2019; 52:2056-2069. [PMID: 31310504 DOI: 10.1021/acs.accounts.9b00216] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Pentacene shows unique electronic properties that have long been appreciated and exploited. Over the past 20 years, new synthetic schemes have been developed to address some of the problems encountered with pristine pentacene (e.g., stability and solubility), and pentacene derivatives have become a mainstay in the realm of organic semiconductors in applications such as organic light-emitting diodes, organic field-effect transistors (OFETs), and organic photovoltaics. At the onset of our work, the vast majority of known pentacene derivatives featured a symmetrical structure, often as the result of synthetic protocols that rely on nucleophilic additions to 6,13-pentacenequinone (PQ). The assembly of pentacenes featuring an unsymmetrical framework held great appeal, but the stepwise formation of derivatives, in which a specific function might be incorporated through each individual addition step, did not exist. This Account presents contributions from our lab and others to the synthesis and study of unsymmetrical pentacene derivatives. PQ offers an ideal platform for desymmetrization through the sequential addition of nucleophiles to each of the two ketone groups. Addition can be completed in a one-pot protocol, or through individual steps in which the product of the first addition is isolated and used as a precursor in the divergent synthesis of a series of structurally related molecules. This general approach has been used to assemble pentacene derivatives appended with alkynyl/aryl/alkyl groups, polarized frameworks via substitution with donor and/or acceptor groups, and conjugated oligomers linked by butadiynyl moieties. Stepwise substitution also provides derivatives with remarkable functionality, including pentacene-porphyrin dyads, pendent TEMPO free radicals, cyanoacrylic acid anchor groups (for incorporation into dye-sensitized solar cells), and derivatives with ambipolar behavior for OFET devices. The study of intramolecular singlet fission (iSF) has emerged as one of the most fruitful applications of unsymmetrical pentacene derivatives. SF involves the spontaneous splitting of a photoexcited singlet state (S1) in one chromophore into a pair of triplets (T1) shared with a neighboring chromophore. Pentacene derivatives are particularly well suited for this since E(S1) ≥ 2E(T1) satisfies the thermodynamic requirements for SF, and they have the additional feature that two chromophores can be tethered together by a "spacer" that allows spectroscopic studies of iSF to be done in dilute solution. From a synthetic perspective, the major advantage of the dimeric structure is the ability to modify the spacer, which allows for control over the distance, geometric relationship, and electronic coupling between the two pentacene groups. Dimeric pentacenes are central to providing an in-depth understanding of the molecular mechanism of SF, often providing advances not possible from measurements in the solid state.
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Affiliation(s)
- Rik R. Tykwinski
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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