1
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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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2
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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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3
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Mencaroni L, Elisei F, Marrocchi A, Spalletti A, Carlotti B. Intramolecular Singlet Fission Coupled with Intermolecular Triplet Separation as a Strategy to Achieve High Triplet Yields in Fluorene-Based Small Molecules. J Phys Chem B 2024; 128:3442-3453. [PMID: 38544417 DOI: 10.1021/acs.jpcb.4c00194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
In this work, detailed experimental proof and in-depth analysis of the singlet fission (SF) mechanism, operative in fluorene-based small molecules, are carried out by employing advanced time-resolved spectroscopies with nanosecond and femtosecond resolution. The investigation of the effect of solution concentration and solvent viscosity together with temperature and excitation wavelength demonstrates INTRAmolecular formation of the correlated triplet pair followed by INTERmolecular independent triplet separation via a "super-diffusional" triplet-triplet transfer process. This unconventional INTRA- to INTERmolecular SF may be considered an "ideal" mechanism. Indeed, intramolecular formation of the correlated triplet pair is here interestingly proved for small molecules rather than large multichromophoric systems, allowing easy synthesis and processability while maintaining good control over the SF process. On the other hand, the intermolecular triplet separation may be exploited to achieve high triplet quantum yields in these new SF small molecules.
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Affiliation(s)
- Letizia Mencaroni
- Department of Chemistry, Biology and Biotechnology and CEMIN, University of Perugia, via dell'Elce di sotto n.8, Perugia 06123, Italy
| | - Fausto Elisei
- Department of Chemistry, Biology and Biotechnology and CEMIN, University of Perugia, via dell'Elce di sotto n.8, Perugia 06123, Italy
| | - Assunta Marrocchi
- Department of Chemistry, Biology and Biotechnology and CEMIN, University of Perugia, via dell'Elce di sotto n.8, Perugia 06123, Italy
| | - Anna Spalletti
- Department of Chemistry, Biology and Biotechnology and CEMIN, University of Perugia, via dell'Elce di sotto n.8, Perugia 06123, Italy
| | - Benedetta Carlotti
- Department of Chemistry, Biology and Biotechnology and CEMIN, University of Perugia, via dell'Elce di sotto n.8, Perugia 06123, Italy
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4
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Wang Z, Xie X, Ma H. Simultaneous Intra- and Intermolecular Singlet Fission in Bipentacene Macrocycle Aggregates. J Phys Chem Lett 2024; 15:3523-3530. [PMID: 38522085 DOI: 10.1021/acs.jpclett.4c00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Singlet fission (SF) is a process where a singlet state splits into two triplet states, which is essential for enhancing optoelectronic devices. Macrocyclic structures allow for precise control of chromophore orientation and facilitate singlet fission in solutions. However, the behavior of these structures in thin films, crucial for solid-state device optimization, remains underexplored. This study examines the aggregation and singlet fission processes of bipentacene macrocycles (BPc) in thin films using molecular dynamics simulations and electronic structure calculations. Findings indicate that BPc aggregates more rapidly with less chloroform, aligning parallel to the substrate. Intramolecular singlet fission (iSF) rates are rarely changed during evaporation, but the efficiency of intermolecular singlet fission (xSF) improves due to the increase in packing domains, suggesting that orderly crystal domains are not necessary for device efficiency. This opens avenues for varied device designs and traditional solution-based methods for optimal device development.
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Affiliation(s)
- Zhangxia Wang
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Xiaoyu Xie
- Qingdao Institute for Theoretical and Computational Sciences, School of Chemistry and Chemical Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Haibo Ma
- Qingdao Institute for Theoretical and Computational Sciences, School of Chemistry and Chemical Engineering, Shandong University, Qingdao, Shandong 266237, China
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5
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Wega J, Zhang KF, Lacour J, Vauthey E. Controlling Symmetry-Breaking Charge Separation in Pyrene Bichromophores. J Phys Chem Lett 2024:2834-2840. [PMID: 38442038 DOI: 10.1021/acs.jpclett.4c00337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
So far, symmetry-breaking charge separation (SB-CS) has been observed with a limited number of chromophores and is usually inhibited by the formation of an excimer. , We show here that thanks to of fine-tuning of the interchromophore coupling via structural control, SB-CS can be operative with pyrene, despite its high propensity to form an excimer. This is realized with a bichromophoric system consisting of two pyrenes attached to a crown ether macrocycle, which can bind cations of different sizes. By combining stationary and time-resolved spectroscopy together with molecular dynamics simulations, we demonstrate that the excited-state dynamics can be totally changed depending on the binding cation. Whereas strong coupling leads to rapid excimer formation, too weak coupling results in noninteracting chromophores. However, intermediate coupling, achieved upon binding of Mg2+, allows for SB-CS to be operative.
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6
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Greißel PM, Thiel D, Gotfredsen H, Chen L, Krug M, Papadopoulos I, Miskolzie M, Torres T, Clark T, Brøndsted Nielsen M, Tykwinski RR, Guldi DM. Intramolecular Triplet Diffusion Facilitates Triplet Dissociation in a Pentacene Hexamer. Angew Chem Int Ed Engl 2024; 63:e202315064. [PMID: 38092707 DOI: 10.1002/anie.202315064] [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: 10/07/2023] [Indexed: 01/26/2024]
Abstract
Triplet dynamics in singlet fission depend strongly on the strength of the electronic coupling. Covalent systems in solution offer precise control over such couplings. Nonetheless, efficient free triplet generation remains elusive in most systems, as the intermediate triplet pair 1 (T1 T1 ) is prone to triplet-triplet annihilation due to its spatial confinement. In the solid state, entropically driven triplet diffusion assists in the spatial separation of triplets, resulting in higher yields of free triplets. Control over electronic coupling in the solid state is, however, challenging given its sensitivity to molecular packing. We have thus developed a hexameric system (HexPnc) to enable solid-state-like triplet diffusion at the molecular scale. This system is realized by covalently tethering three pentacene dimers to a central subphthalocyanine scaffold. Transient absorption spectroscopy, complemented by theoretical structural optimizations and steady-state spectroscopy, reveals that triplet diffusion is indeed facilitated due to intramolecular cluster formation. The yield of free triplets in HexPnc is increased by a factor of up to 14 compared to the corresponding dimeric reference (DiPnc). Thus, HexPnc establishes crucial design aspects for achieving efficient triplet dissociation in strongly coupled systems by providing avenues for diffusive separation of 1 (T1 T1 ), while, concomitantly, retaining strong interchromophore coupling which preserves rapid formation of 1 (T1 T1 ).
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Affiliation(s)
- Phillip M Greißel
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Dominik Thiel
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Henrik Gotfredsen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
- Current address: Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, UK
| | - Lan Chen
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Marcel Krug
- Department of Chemistry and Pharmacy &, Interdisciplinary Center for Molecular Materials (ICMM), Friedrich-Alexander-University Erlangen-Nuremberg, Egerlandstraße 3, 91058, Erlangen, Germany
| | - Ilias Papadopoulos
- Department of Chemistry and Pharmacy &, 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 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Mark Miskolzie
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Tomás Torres
- Department of Organic Chemistry, Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049, Madrid, Spain
- IMDEA Nanociencia, C/Faraday 9, Cantoblanco, 28049, Madrid, Spain
| | - Timothy Clark
- Department of Chemistry and Pharmacy &, Computer-Chemie-Center (CCC), Friedrich-Alexander-University Erlangen-Nuremberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Mogens Brøndsted Nielsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen Ø, Denmark
| | - Rik R Tykwinski
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta, T6G 2G2, Canada
| | - Dirk M Guldi
- 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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7
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Yan Y, Brega V, Pina MM, Thomas SW. Electronic effects of conjugated aryl groups on the properties and reactivities of di(arylethynyl)tetracenes. Org Biomol Chem 2024; 22:289-295. [PMID: 38054249 DOI: 10.1039/d3ob01601c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
The photochemical oxidations of acenes can cause challenges with their optoelectronic applications, such as singlet fission and organic transistors. At the same time, these reactions form the basis for many luminescent sensing schemes for 1O2. While diethynyl substitution is arguably the most widely adopted of the various substitution strategies to control oxidation and also improve solubility and processability of long acenes, the extent to which differences between the alkyne groups can influence key properties of long acenes remains largely unknown. This report therefore describes the effects of various arenes and heteroarenes on the electronic structures, optical properites, and reactivity with singlet oxygen for eight 5,12-di(arylethynyl)tetracenes. The fluorescence spectra of these tetracenes span approximately 100 nm, while their observed rate constants for reaction with singlet oxygen correlates strongly with the HOMO level, spanning one order of magnitude. They are also amenable to fluorescent materials that respond ratiometrically to singlet oxygen. Therefore, electronic effects of groups directly conjugated to ethynylacenes offer a useful chemical space for rational acene design.
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Affiliation(s)
- Yu Yan
- Department of Chemistry, Tufts University, Medford, MA 02155, USA.
| | - Valentina Brega
- Department of Chemistry, Tufts University, Medford, MA 02155, USA.
| | - Manuel M Pina
- Department of Chemistry, Tufts University, Medford, MA 02155, USA.
| | - Samuel W Thomas
- Department of Chemistry, Tufts University, Medford, MA 02155, USA.
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8
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He G, Parenti KR, Budden PJ, Niklas J, Macdonald T, Kumarasamy E, Chen X, Yin X, McCamey DR, Poluektov OG, Campos LM, Sfeir MY. Unraveling Triplet Formation Mechanisms in Acenothiophene Chromophores. J Am Chem Soc 2023; 145:22058-22068. [PMID: 37787467 DOI: 10.1021/jacs.3c07082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
The evolution of molecular platforms for singlet fission (SF) chromophores has fueled the quest for new compounds capable of generating triplets quantitatively at fast time scales. As the exploration of molecular motifs for SF has diversified, a key challenge has emerged in identifying when the criteria for SF have been satisfied. Here, we show how covalently bound molecular dimers uniquely provide a set of characteristic optical markers that can be used to distinguish triplet pair formation from processes that generate an individual triplet. These markers are contained within (i) triplet charge-transfer excited state absorption features, (ii) kinetic signatures of triplet-triplet annihilation processes, and (iii) the modulation of triplet formation rates using bridging moieties between chromophores. Our assignments are verified by time-resolved electron paramagnetic resonance (EPR) measurements, which directly identify triplet pairs by their electron spin and polarization patterns. We apply these diagnostic criteria to dimers of acenothiophene derivatives in solution that were recently reported to undergo efficient intermolecular SF in condensed media. While the electronic structure of these heteroatom-containing chromophores can be broadly tuned, the effect of their enhanced spin-orbit coupling and low-energy nonbonding orbitals on their SF dynamics has not been fully determined. We find that SF is fast and efficient in tetracenothiophene but that anthradithiophene exhibits fast intersystem crossing due to modifications of the singlet and triplet excited state energies upon functionalization of the heterocycle. We conclude that it is not sufficient to assign SF based on comparisons of the triplet formation kinetics between monomer and multichromophore systems.
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Affiliation(s)
- 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
| | - Kaia R Parenti
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Peter J Budden
- 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
| | - Jens Niklas
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Thomas Macdonald
- ARC Centre of Excellence in Exciton Science, School of Physics, UNSW Sydney, Sydney, 2052 NSW, Australia
| | - Elango Kumarasamy
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Xing Chen
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China
| | - Xiaodong Yin
- Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China
| | - Dane R McCamey
- ARC Centre of Excellence in Exciton Science, School of Physics, UNSW Sydney, Sydney, 2052 NSW, Australia
| | - Oleg G Poluektov
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Luis M Campos
- 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
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9
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He G, Churchill EM, Parenti KR, Zhang J, Narayanan P, Namata F, Malkoch M, Congreve DN, Cacciuto A, Sfeir MY, Campos LM. Promoting multiexciton interactions in singlet fission and triplet fusion upconversion dendrimers. Nat Commun 2023; 14:6080. [PMID: 37770472 PMCID: PMC10539328 DOI: 10.1038/s41467-023-41818-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 09/20/2023] [Indexed: 09/30/2023] Open
Abstract
Singlet fission and triplet-triplet annihilation upconversion are two multiexciton processes intimately related to the dynamic interaction between one high-lying energy singlet and two low-lying energy triplet excitons. Here, we introduce a series of dendritic macromolecules that serve as platform to study the effect of interchromophore interactions on the dynamics of multiexciton generation and decay as a function of dendrimer generation. The dendrimers (generations 1-4) consist of trimethylolpropane core and 2,2-bis(methylol)propionic acid (bis-MPA) dendrons that provide exponential growth of the branches, leading to a corona decorated with pentacenes for SF or anthracenes for TTA-UC. The findings reveal a trend where a few highly ordered sites emerge as the dendrimer generation grows, dominating the multiexciton dynamics, as deduced from optical spectra, and transient absorption spectroscopy. While the dendritic structures enhance TTA-UC at low annihilator concentrations in the largest dendrimers, the paired chromophore interactions induce a broadened and red-shifted excimer emission. In SF dendrimers of higher generations, the triplet dynamics become increasingly dominated by pairwise sites exhibiting strong coupling (Type II), which can be readily distinguished from sites with weaker coupling (Type I) by their spectral dynamics and decay kinetics.
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Affiliation(s)
- Guiying He
- Department of Physics, Graduate Center, City University of New York, New York, NY, 10016, USA
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA
| | - Emily M Churchill
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Kaia R Parenti
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Jocelyn Zhang
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Pournima Narayanan
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
- Department of Chemistry, Stanford University, Stanford, CA, 94305, USA
| | - Faridah Namata
- KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, SE-100 44, Stockholm, Sweden
| | - Michael Malkoch
- KTH Royal Institute of Technology, Department of Fibre and Polymer Technology, SE-100 44, Stockholm, Sweden
| | - Daniel N Congreve
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Angelo Cacciuto
- Department of Chemistry, Columbia University, New York, NY, 10027, USA
| | - Matthew Y Sfeir
- Department of Physics, Graduate Center, City University of New York, New York, NY, 10016, USA.
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York, NY, 10031, USA.
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, NY, 10027, USA.
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10
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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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11
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Wang YC, Feng S, Kong Y, Huang X, Liang W, Zhao Y. Electronic Couplings for Singlet Fission Processes Based on the Fragment Particle-Hole Densities. J Chem Theory Comput 2023. [PMID: 37296507 DOI: 10.1021/acs.jctc.3c00243] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A new diabatization scheme is proposed to calculate the electronic couplings for the singlet fission process in multichromophoric systems. In this approach, a robust descriptor that treats single and multiple excitations on an equal footing is adopted to quantify the localization degree of the particle and hole densities of the electronic states. By maximally localizing the particles and holes in terms of predefined molecular fragments, quasi-diabatic states with well-defined characters (locally excited, charge transfer, correlated triplet pair, etc.) can be automatically constructed as the linear combinations of the adiabatic ones, and the electronic couplings can be directly obtained. This approach is very general in that it applies to electronic states with various spin multiplicities and can be combined with various kinds of preliminary electronic structure calculations. Due to the high numerical efficiency, it is able to manipulate more than 100 electronic states in diabatization. The applications to the tetracene dimer and trimer reveal that high-lying multiply excited charge transfer states have significant influences on both the formation and separation of the correlated triplet pair and can even enlarge the coupling for the latter process by 1 order of magnitude.
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Affiliation(s)
- Yu-Chen Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Shishi Feng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Yi Kong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Xunkun Huang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - WanZhen Liang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
| | - Yi Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China
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12
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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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13
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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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14
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Kishida S, Takano M, Sekiya T, Ukaji Y, Endo K. Cyclopropenes for the Stepwise Synthesis of 1,2,4,5-Tetraarylbenzenes via 1,4-Cyclohexadienes. J Org Chem 2022; 87:14833-14839. [PMID: 36201259 DOI: 10.1021/acs.joc.2c01261] [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
This paper describes a synthetic approach to the synthesis of 1,2,4,5-tetraarylbenzene derivatives from cyclopropenes. The Lewis acid-mediated dimerization of cyclopropenes gives tricyclo[3.1.0.02,4]hexane derivatives. The subsequent thermal ring-opening reaction under solvent-free conditions gives 1,4-cyclohexadienes bearing quaternary carbons. The novel Br2-mediated oxidative rearrangement of 1,4-cyclohexadienes takes place to give 1,2,4,5-tetraarylbenzene derivatives in high to excellent yields.
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Affiliation(s)
- Satoshi Kishida
- Department of Chemistry, Faculty of Science, Tokyo University of Science, Tokyo 162-8601, Japan
| | - Misaki Takano
- Department of Chemistry, Faculty of Science, Tokyo University of Science, Tokyo 162-8601, Japan
| | - Takuya Sekiya
- Division of Material Chemistry, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192, Japan
| | - Yutaka Ukaji
- Division of Material Chemistry, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192, Japan
| | - Kohei Endo
- Department of Chemistry, Faculty of Science, Tokyo University of Science, Tokyo 162-8601, Japan
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15
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Hu Z, Sun X. All-Atom Nonadiabatic Semiclassical Mapping Dynamics for Photoinduced Charge Transfer of Organic Photovoltaic Molecules in Explicit Solvents. J Chem Theory Comput 2022; 18:5819-5836. [PMID: 36073792 DOI: 10.1021/acs.jctc.2c00631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Direct all-atom simulation of nonadiabatic dynamics in disordered condensed phases like liquid solutions and amorphous solids has been challenging. The first all-atom simulation of the photoinduced charge-transfer dynamics of a prototypical organic photovoltaic carotenoid-porphyrin-C60 molecular triad in explicit tetrahydrofuran is presented. Based on the Meyer-Miller mapping Hamiltonian, various semiclassical and mixed quantum-classical dynamics are employed, including the linearized semiclassical, symmetrical quasiclassical, mean-field Ehrenfest, classical mapping model, and spin-mapping model approaches. The all-atom nonadiabatic dynamics were compared to multi-state harmonic models with a globally shared bath, and the models built using the ensemble averages on the initial electronic state could reproduce the all-atom results. The solvent effect was found to be critical for the photoinduced charge transfer, and the time-dependent solute-solvent radial distribution functions revealed that only the nonadiabatic dynamics started with the effective forces on the initial electronic state could capture the correct nuclear dynamics. The proposed strategy for modeling condensed-phase nonadiabatic dynamics with atomistic details is readily applied to complex condensed-phase systems.
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Affiliation(s)
- Zhubin Hu
- Division of Arts and Sciences, New York University Shanghai, 1555 Century Avenue, Shanghai 200122, China.,NYU-ECNU Center for Computational Chemistry, New York University Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China.,State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Xiang Sun
- Division of Arts and Sciences, New York University Shanghai, 1555 Century Avenue, Shanghai 200122, China.,NYU-ECNU Center for Computational Chemistry, New York University Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China.,State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China.,Department of Chemistry, New York University, New York, New York 10003, United States
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16
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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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17
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He G, Yablon LM, Parenti KR, Fallon KJ, Campos LM, Sfeir MY. Quantifying Exciton Transport in Singlet Fission Diblock Copolymers. J Am Chem Soc 2022; 144:3269-3278. [PMID: 35166107 DOI: 10.1021/jacs.1c13456] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Singlet fission (SF) is a mechanism of exciton multiplication in organic chromophores, which has potential to drive highly efficient optoelectronic devices. Creating effective device architectures that operate by SF critically depends on electronic interactions across multiple length scales─from individual molecules to interchromophore interactions that facilitate multiexciton dephasing and exciton diffusion toward donor-acceptor interfaces. Therefore, it is imperative to understand the underpinnings of multiexciton transport and interfacial energy transfer in multichromophore systems. Interestingly, block copolymers (BCPs) can be designed to control multiscale interactions by tailoring the nature of the building blocks, yet SF dynamics are not well understood in these macromolecules. Here, we designed diblock copolymers comprising an inherent energy cleft at the interface between a block with pendent pentacene chromophores and an additional block with pendent tetracene chromophores. The singlet and triplet energy offset between the two blocks creates a driving force for exciton transport along the BCP chain in dilute solution. Using time-resolved optical spectroscopy, we have quantified the yields of key energy transfer steps, including both singlet and triplet energy transfer processes across the pentacene-tetracene interface. From this modular BCP architecture, we correlate the energy transfer time scales and relative yields with the length of each block. The ability to quantify these energy transfer processes provides valuable insights into exciton transport at critical length scales between bulk crystalline systems and small-molecule dimers─an area that has been underexplored.
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Affiliation(s)
- 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
| | - Lauren M Yablon
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Kaia R Parenti
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Kealan J Fallon
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Luis M Campos
- 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
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18
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Paul S, Karunakaran V. Excimer Formation Inhibits the Intramolecular Singlet Fission Dynamics: Systematic Tilting of Pentacene Dimers by Linking Positions. J Phys Chem B 2022; 126:1054-1062. [PMID: 35107283 DOI: 10.1021/acs.jpcb.1c07951] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The role of excimer formation in inhibiting or enhancing the efficiency of the intramolecular singlet fission (iSF) process has been a subject of recent debate. Here, we investigated the effect of excimer formation on iSF dynamics by modifying its configuration by connecting pentacenes at various positions. Hence, pentacene dimers having slip-stacked (2,2' BP, J-type), oblique (2,6' BP), and facial (6,6' BP, H-type) configurations were synthesized by covalently linking pentacenes at positions 2,2', 2,6', and 6,6', respectively, with an ethynyl bridge, and their ultrafast excited-state relaxation dynamics were characterized. Femtosecond time-resolved transient absorption spectra revealed that the efficiency of iSF dynamics decreased from slip-stacked (182%) to oblique configuration (97%),whereas in the 6,6' BP with facial configuration, strong electronic coupling led to the formation of excimers that decayed nonradiatively without formation of correlated triplet pairs. These studies reveal the formation of excimers by strong intrapentacene electronic coupling upon ultrafast excitation, preventing the efficient iSF process.
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Affiliation(s)
- Sumitha Paul
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala 695 019, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Venugopal Karunakaran
- Photosciences and Photonics Section, Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala 695 019, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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19
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Mencaroni L, Carlotti B, Elisei F, Marrocchi A, Spalletti A. Exploring a new class of singlet fission fluorene derivatives with high-energy triplets. Chem Sci 2022; 13:2071-2078. [PMID: 35308848 PMCID: PMC8848920 DOI: 10.1039/d1sc07175k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 01/24/2022] [Indexed: 11/21/2022] Open
Abstract
We found that a stronger push–pull character favours SF, as long as the ICT does not act as a trap. The unique property of generating high-energy triplets (ca. 2 eV) via SF makes these materials outstanding candidates for photovoltaic applications.
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Affiliation(s)
- Letizia Mencaroni
- Department of Chemistry Biology and Biotechnology and CEMIN, University of Perugia, via elce di sotto n. 8, 06123, Perugia, Italy
| | - Benedetta Carlotti
- Department of Chemistry Biology and Biotechnology and CEMIN, University of Perugia, via elce di sotto n. 8, 06123, Perugia, Italy
| | - Fausto Elisei
- Department of Chemistry Biology and Biotechnology and CEMIN, University of Perugia, via elce di sotto n. 8, 06123, Perugia, Italy
| | - Assunta Marrocchi
- Department of Chemistry Biology and Biotechnology and CEMIN, University of Perugia, via elce di sotto n. 8, 06123, Perugia, Italy
| | - Anna Spalletti
- Department of Chemistry Biology and Biotechnology and CEMIN, University of Perugia, via elce di sotto n. 8, 06123, Perugia, Italy
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20
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Hong Y, Kim J, Kim D, Kim H. Theoretical Engineering of Singlet Fission Kinetics in Perylene Bisimide Dimer with Chromophore Rotation. J Phys Chem A 2021; 125:875-884. [DOI: 10.1021/acs.jpca.0c08706] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Yongseok Hong
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Republic of Korea
| | - Juno Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Republic of Korea
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul 03722, Republic of Korea
| | - Hyungjun Kim
- Department of Chemistry, Quantum Chemistry Laboratory, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Research Institute of Basic Sciences, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
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21
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He G, Busby E, Appavoo K, Wu Q, Xia J, Campos LM, Sfeir MY. Charge transfer states impact the triplet pair dynamics of singlet fission polymers. J Chem Phys 2020; 153:244902. [PMID: 33380093 DOI: 10.1063/5.0029858] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Polymers are desirable optoelectronic materials, stemming from their solution processability, tunable electronic properties, and large absorption coefficients. An exciting development is the recent discovery that singlet fission (SF), the conversion of a singlet exciton to a pair of triplet states, can occur along the backbone of an individual conjugated polymer chain. Compared to other intramolecular SF compounds, the nature of the triplet pair state in SF polymers remains poorly understood, hampering the development of new materials with optimized excited state dynamics. Here, we investigate the effect of solvent polarity on the triplet pair dynamics in the SF polymer polybenzodithiophene-thiophene-1,1-dioxide. We use transient emission measurements to study isolated polymer chains in solution and use the change in the solvent polarity to investigate the role of charge transfer character in both the singlet exciton and the triplet pair multiexciton. We identify both singlet fluorescence and direct triplet pair emission, indicating significant symmetry breaking. Surprisingly, the singlet emission peak is relatively insensitive to solvent polarity despite its nominal "charge-transfer" nature. In contrast, the redshift of the triplet pair energy with increasing solvent polarity indicates significant charge transfer character. While the energy separation between singlet and triplet pair states increases with solvent polarity, the overall SF rate constant depends on both the energetic driving force and additional environmental factors. The triplet pair lifetime is directly determined by the solvent effect on its overall energy. The dominant recombination channel is a concerted, radiationless decay process that scales as predicted by a simple energy gap law.
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Affiliation(s)
- Guiying He
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, USA
| | - Erik Busby
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Kannatassen Appavoo
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Qin Wu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Jianlong Xia
- School of Chemistry, Chemical Engineering and Life Science; State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China
| | - Luis M Campos
- Department of Chemistry, Columbia University, New York, New York 10027, USA
| | - Matthew Y Sfeir
- Department of Physics, Graduate Center, City University of New York, New York, New York 10016, USA
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22
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Carreras A, Jiang H, Pokhilko P, Krylov AI, Zimmerman PM, Casanova D. Calculation of spin–orbit couplings using RASCI spinless one-particle density matrices: Theory and applications. J Chem Phys 2020; 153:214107. [DOI: 10.1063/5.0029146] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Abel Carreras
- Donostia International Physics Center (DIPC), Manuel de Lardizabal Pasalekua 4, 20018 Donostia, Euskadi, Spain
| | - Hanjie Jiang
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Pavel Pokhilko
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Anna I. Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA
| | - Paul M. Zimmerman
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - David Casanova
- Donostia International Physics Center (DIPC), Manuel de Lardizabal Pasalekua 4, 20018 Donostia, Euskadi, Spain
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