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Petropoulos V, Rukin PS, Quintela F, Russo M, Moretti L, Moore A, Moore T, Gust D, Prezzi D, Scholes GD, Molinari E, Cerullo G, Troiani F, Rozzi CA, Maiuri M. Vibronic Coupling Drives the Ultrafast Internal Conversion in a Functionalized Free-Base Porphyrin. J Phys Chem Lett 2024; 15:4461-4467. [PMID: 38630018 DOI: 10.1021/acs.jpclett.4c00372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Internal conversion (IC) is a common radiationless transition in polyatomic molecules. Theory predicts that molecular vibrations assist IC between excited states, and ultrafast experiments can provide insight into their structure-function relationship. Here we elucidate the dynamics of the vibrational modes driving the IC process within the Q band of a functionalized porphyrin molecule. Through a combination of ultrafast multidimensional spectroscopies and theoretical modeling, we observe a 60 fs Qy-Qx IC and demonstrate that it is driven by the interplay among multiple high-frequency modes. Notably, we identify 1510 cm-1 as the leading tuning mode that brings the porphyrin to an optimal geometry for energy surface crossing. By employing coherent wave packet analysis, we highlight a set of short-lived vibrations (1200-1400 cm-1), promoting the IC within ≈60 fs. Furthermore, we identify one coupling mode (1350 cm-1) that is responsible for vibronic mixing within the Q states. Our findings indicate that porphyrin-core functionalization modulates IC effectively, offering new opportunities in photocatalysis and optoelectronics.
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Affiliation(s)
- Vasilis Petropoulos
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Pavel S Rukin
- CNR - Istituto Nanoscienze, Via Campi 213A, I-41125 Modena, Italy
| | - Frank Quintela
- Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università degli Studi di Modena e Reggio Emilia, via G. Campi 213A, I-41125 Modena, Italy
| | - Mattia Russo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Luca Moretti
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Ana Moore
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Thomas Moore
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Devens Gust
- School of Molecular Sciences, Arizona State University, Tempe, Arizona 85287, United States
| | - Deborah Prezzi
- CNR - Istituto Nanoscienze, Via Campi 213A, I-41125 Modena, Italy
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08540, United States
| | - Elisa Molinari
- CNR - Istituto Nanoscienze, Via Campi 213A, I-41125 Modena, Italy
- Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università degli Studi di Modena e Reggio Emilia, via G. Campi 213A, I-41125 Modena, Italy
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Filippo Troiani
- CNR - Istituto Nanoscienze, Via Campi 213A, I-41125 Modena, Italy
| | - Carlo A Rozzi
- CNR - Istituto Nanoscienze, Via Campi 213A, I-41125 Modena, Italy
| | - Margherita Maiuri
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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2
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Rukin P, Prezzi D, Rozzi CA. Excited-state normal-mode analysis: The case of porphyrins. J Chem Phys 2023; 159:244103. [PMID: 38131481 DOI: 10.1063/5.0173336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 10/14/2023] [Indexed: 12/23/2023] Open
Abstract
We systematically applied excited-state normal mode analysis to investigate and compare the relaxation and internal conversion dynamics of a free-base porphyrin (BP) with those of a novel functional porphyrin (FP) derivative. We discuss the strengths and limitations of this method and employ it to predict very different dynamical behaviors of the two compounds and to clarify the role of high reorganization energy modes in driving the system toward critical regions of the potential energy landscape. We identify the modes of vibrations along which the energy gap between two excited-state potential energy surfaces within the Q band manifold may vanish and find that the excess energy to reach this "touching" region is significantly reduced in the case of FP (0.16 eV) as compared to the one calculated for BP (0.92 eV). Our findings establish a link between the chemical functionalization and the electronic and vibrational structure that can be exploited to control the internal conversion pathways in a systematic way.
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Affiliation(s)
- Pavel Rukin
- S3 Center, Nanoscience Institute - National Research Council (CNR-NANO), Via Campi 213/a, Modena, Italy
| | - Deborah Prezzi
- S3 Center, Nanoscience Institute - National Research Council (CNR-NANO), Via Campi 213/a, Modena, Italy
| | - Carlo Andrea Rozzi
- S3 Center, Nanoscience Institute - National Research Council (CNR-NANO), Via Campi 213/a, Modena, Italy
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Chen M, Guo J, Mo F, Yu W, Fu Y. Highly Sensitive Photoelectrochemical Immunosensor Based on Organic Multielectron Donor Nanocomposite as Signal Probe. Anal Chem 2022; 94:17039-17045. [PMID: 36455203 DOI: 10.1021/acs.analchem.2c02967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Organic photoelectric materials with conjugated electron-rich structures and good biocompatibilities have broad application prospects in biosensors. Herein, we report a promising organic photoelectric multielectron donor nanocomposite for highly sensitive PEC immunoassays. Specifically, the organic multielectron donor nanocomposite (DA-ZnTCPP-g-C3N4) was prepared from dopamine (DA, polyphenol hydroxyl structure substance), zinc tetracarboxylate porphyrin (ZnTCPP, large p-π conjugated heterocyclic compound), and two-dimensional graphene-like nitrogen carbide (g-C3N4) via an amidation reaction. With a multielectron donor structure and photoelectricity, this nanocomposite can achieve sensitization by self-structure without the addition of an electron donor in the test solution. It was utilized to label the carcinoembryonic detection antibody as a immuno-probe (Ab2-DA-ZnTCPP-g-C3N4). Meanwhile, the glassy carbon electrode electrodeposited with gold nanoparticles anchoring the capture antibody was used as a PEC immunomatrix (Ab1/DpAu/GCE). The enhanced PEC current, "signal on", was confirmed by the immunosensor via sandwich immunorecognition of a carcinoembryonic antigen (CEA). Under optimal conditions, the as-prepared sensing platform displayed high sensitivity for CEA with a dynamic linear response range from 10 fg·mL-1 to 1 mg·mL-1 and a lower detection limit of 3.6 fg·mL-1. This organic nanocomposite showed good sensitivity and stability in an immunosensing system with a low background. This strategy affords a promising approach for biological applications of organic photoelectric materials.
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Affiliation(s)
- Min Chen
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Jiang Guo
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Fangjing Mo
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Wanqing Yu
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Yingzi Fu
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
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Roy P, Kundu S, Makri N, Fleming GR. Interference between Franck-Condon and Herzberg-Teller Terms in the Condensed-Phase Molecular Spectra of Metal-Based Tetrapyrrole Derivatives. J Phys Chem Lett 2022; 13:7413-7419. [PMID: 35929598 PMCID: PMC9393888 DOI: 10.1021/acs.jpclett.2c01963] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/02/2022] [Indexed: 06/15/2023]
Abstract
The commonly used Franck-Condon (FC) approximation is inadequate for explaining the electronic spectra of compounds that possess vibrations with substantial Herzberg-Teller (HT) couplings. Metal-based tetrapyrrole derivatives, which are ubiquitous natural pigments, often exhibit prominent HT activity. In this paper, we compare the condensed phase spectra of zinc-tetraphenylporphyrin (ZnTPP) and zinc-phthalocyanine (ZnPc), which exhibit vastly different spectral features in spite of sharing a common tetrapyrrole backbone. The absorption and emission spectra of ZnTPP are characterized by a lack of mirror symmetry and nontrivial temperature dependence. In contrast, mirror symmetry is restored, and the nontrivial temperature-dependent features disappear in ZnPc. We attribute these differences to FC-HT interference, which is less pronounced in ZnPc because of a larger FC component in the dipole moment that leads to FC-dominated transitions. A single minimalistic FC-HT vibronic model reproduces all the experimental spectral features of these molecules. These observations suggest that FC-HT interference is highly susceptible to chemical modification.
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Affiliation(s)
- Partha
Pratim Roy
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli
Energy Nanoscience Institute at Berkeley, Berkeley, California 94720, United States
| | - Sohang Kundu
- Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Nancy Makri
- Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Physics, University of Illinois, Urbana, Illinois 61801, United States
- Illinois
Quantum Information Science & Technology Center, University of Illinois, Urbana, Illinois 61801, United States
| | - Graham R. Fleming
- Department
of Chemistry, University of California,
Berkeley, Berkeley, California 94720, United States
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli
Energy Nanoscience Institute at Berkeley, Berkeley, California 94720, United States
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Roy P, Kundu S, Valdiviezo J, Bullard G, Fletcher JT, Liu R, Yang SJ, Zhang P, Beratan DN, Therien MJ, Makri N, Fleming GR. Synthetic Control of Exciton Dynamics in Bioinspired Cofacial Porphyrin Dimers. J Am Chem Soc 2022; 144:6298-6310. [PMID: 35353523 PMCID: PMC9011348 DOI: 10.1021/jacs.1c12889] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Indexed: 11/29/2022]
Abstract
Understanding how the complex interplay among excitonic interactions, vibronic couplings, and reorganization energy determines coherence-enabled transport mechanisms is a grand challenge with both foundational implications and potential payoffs for energy science. We use a combined experimental and theoretical approach to show how a modest change in structure may be used to modify the exciton delocalization, tune electronic and vibrational coherences, and alter the mechanism of exciton transfer in covalently linked cofacial Zn-porphyrin dimers (meso-beta linked ABm-β and meso-meso linked AAm-m). While both ABm-β and AAm-m feature zinc porphyrins linked by a 1,2-phenylene bridge, differences in the interporphyrin connectivity set the lateral shift between macrocycles, reducing electronic coupling in ABm-β and resulting in a localized exciton. Pump-probe experiments show that the exciton dynamics is faster by almost an order of magnitude in the strongly coupled AAm-m dimer, and two-dimensional electronic spectroscopy (2DES) identifies a vibronic coherence that is absent in ABm-β. Theoretical studies indicate how the interchromophore interactions in these structures, and their system-bath couplings, influence excitonic delocalization and vibronic coherence-enabled rapid exciton transport dynamics. Real-time path integral calculations reproduce the exciton transfer kinetics observed experimentally and find that the linking-modulated exciton delocalization strongly enhances the contribution of vibronic coherences to the exciton transfer mechanism, and that this coherence accelerates the exciton transfer dynamics. These benchmark molecular design, 2DES, and theoretical studies provide a foundation for directed explorations of nonclassical effects on exciton dynamics in multiporphyrin assemblies.
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Affiliation(s)
- Partha
Pratim Roy
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli
Energy Nanoscience Institute at Berkeley, Berkeley, California 94720, United States
| | - Sohang Kundu
- Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
| | - Jesús Valdiviezo
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department
of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, United States
| | - George Bullard
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - James T. Fletcher
- Department
of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Rui Liu
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Shiun-Jr Yang
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Peng Zhang
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - David N. Beratan
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department
of Physics, Duke University, Durham, North Carolina 27708, United States
- Department
of Biochemistry, Duke University, Durham, North Carolina 27710, United States
| | - Michael J. Therien
- Department
of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Nancy Makri
- Department
of Chemistry, University of Illinois, Urbana, Illinois 61801, United States
- Department
of Physics, University of Illinois, Urbana, Illinois 61801, United States
- Illinois
Quantum Information Science & Technology Center, University of Illinois, Urbana, Illinois 61801, United States
| | - Graham R. Fleming
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Molecular
Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Kavli
Energy Nanoscience Institute at Berkeley, Berkeley, California 94720, United States
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Zeb J, Ran G, Denis PA, Ghani U, Liu J, Yuan Q, Ullah R, Zhu H, Zhang W. Ultrafast dynamics of the liquid deposited blend film of porphyrin donor and perylene diimide acceptor. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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7
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Abstract
Aggregation-induced emission (AIE), usually referring to the phenomenon in which molecules emit more strongly in the aggregate state than in the solution state, is intriguing and promising in various optoelectronic and biosensing applications. In this Perspective, the basic principles that can lead to AIE and experimental evidence to reveal the AIE mechanism of tetraphenyl ethylene (TPE)-type molecules are discussed. AIE is the consequence of two factors: (1) the fast energy dissipation by crossing a conical intersection (CI) in solutions but not in solids results in low luminescence efficiencies in the solutions, and (2) the weak intermolecular coupling and thus slow intermolecular energy/charge transfers in the AIE solids effectively prevent quenching and result in relatively high luminescence efficiencies. The key to AIE is that the luminescence efficiency is tuned by controlling molecules to cross or not to cross a CI by changing the phase of molecules. How fast a molecule can cross a CI is dependent on the energy barrier of isomerization, which can be tuned in many ways, including mechanical or electrical stimuli, in addition to changing phases. Barrier-dependent crossing CI also results in a very important consequence: excitation-wavelength-dependent fluorescence yield within one electronic excited state, an anti-Vavilov's rule phenomenon. In principle, there can be an alternative way to tune luminescence efficiency by manipulating the formation of CIs instead of crossing or not crossing them. This approach relies on the fact that the electronic ground state and the excited state have many different properties, e.g., dipole moment. By tuning the environment, e.g., dielectric constant, to favor or disfavor one state, one may be able to lift or lower the potential surface of one state so that the potential surfaces of two states can vary between intersected and not contacted.
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Affiliation(s)
- Jianxin Guan
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Chengzhen Shen
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Jie Peng
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
| | - Junrong Zheng
- College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China
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Zarrabi N, Bayard BJ, Seetharaman S, Holzer N, Karr P, Ciuti S, Barbon A, Di Valentin M, van der Est A, D'Souza F, Poddutoori PK. A charge transfer state induced by strong exciton coupling in a cofacial μ-oxo-bridged porphyrin heterodimer. Phys Chem Chem Phys 2021; 23:960-970. [PMID: 33367389 DOI: 10.1039/d0cp05783e] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photosensitizers with high energy, long lasting charge-transfer states are important components in systems designed for solar energy conversion by multistep electron transfer. Here, we show that in a push-pull type, μ-oxo-bridged porphyrin heterodimer composed of octaethylporphyrinatoaluminum(iii) and octaethylporphyrinatophosphorus(v), the strong excitonic coupling between the porphyrins and the different electron withdrawing abilities of Al(iii) and P(v) promote the formation of a high energy CT state. Using, an array of optical and magnetic resonance spectroscopic methods along with theoretical calculations, we demonstrate photodynamics of the heterodimer that involves the initial formation of a singlet CT which relaxes to a triplet CT state with a lifetime of ∼130 ps. The high-energy triplet CT state (3CT = 1.68 eV) lasts for nearly 105 μs prior to relaxing to the ground state.
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Affiliation(s)
- Niloofar Zarrabi
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, 1039 University Drive, Duluth, Minnesota 55812, USA.
| | - Brandon J Bayard
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, 1039 University Drive, Duluth, Minnesota 55812, USA.
| | - Sairaman Seetharaman
- Department of Chemistry, University of North Texas, 1155 Union Circle, # 305070, Denton, Texas 76203-5017, USA.
| | - Noah Holzer
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, 1039 University Drive, Duluth, Minnesota 55812, USA.
| | - Paul Karr
- Department of Physical Sciences and Mathematics, Wayne State College, 111 Main Street, Wayne, Nebraska 68787, USA
| | - Susanna Ciuti
- Dipartimento di Scienze Chimiche, Università degli studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Antonio Barbon
- Dipartimento di Scienze Chimiche, Università degli studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Marilena Di Valentin
- Dipartimento di Scienze Chimiche, Università degli studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Art van der Est
- Department of Chemistry, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON L2S 3A1, Canada.
| | - Francis D'Souza
- Department of Chemistry, University of North Texas, 1155 Union Circle, # 305070, Denton, Texas 76203-5017, USA.
| | - Prashanth K Poddutoori
- Department of Chemistry & Biochemistry, University of Minnesota Duluth, 1039 University Drive, Duluth, Minnesota 55812, USA.
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Stevens AL, Awuku S, Ghiggino KP, Hao Y, Novakovic S, Steer RP, White JM. Spectroscopic and Dynamic Properties of Electronically Excited Pendant Porphyrin Polymers with Backbones of Differing Flexibility. J Phys Chem A 2020; 124:10748-10757. [DOI: 10.1021/acs.jpca.0c09501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amy L. Stevens
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N5C9, Canada
| | - Stephen Awuku
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N5C9, Canada
| | - Kenneth P. Ghiggino
- School of Chemistry and ARC Centre of Excellence in Exciton Science, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ying Hao
- School of Chemistry and ARC Centre of Excellence in Exciton Science, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Sacha Novakovic
- School of Chemistry and ARC Centre of Excellence in Exciton Science, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ronald P. Steer
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan S7N5C9, Canada
| | - Jonathan M. White
- School of Chemistry and ARC Centre of Excellence in Exciton Science, University of Melbourne, Parkville, Victoria 3010, Australia
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van Stokkum IHM, Jumper CC, Lee TS, Myahkostupov M, Castellano FN, Scholes GD. Vibronic and excitonic dynamics in perylenediimide dimers and tetramer. J Chem Phys 2020; 153:224101. [PMID: 33317279 DOI: 10.1063/5.0024530] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Broad-band pump-probe spectroscopy combined with global and target analysis is employed to study the vibronic and excitonic dynamics of two dimers and a tetramer of perylenediimides. A simultaneous analysis is developed for two systems that have been measured in the same conditions. This enhances the resolvability of the vibronic and excitonic dynamics of the systems, and the solvent contributions that are common in the experiments. We resolve two oscillations of 1399 cm-1 or 311 cm-1 damped with ≈30/ps involved in vibrational relaxation and two more oscillations of 537 cm-1 or 136 cm-1 damped with ≈3/ps. A relaxation process with a rate of 2.1/ps-3.2/ps that is positively correlated with the excitonic coupling was discovered in all three model systems, attributed to annihilation of the one but lowest exciton state.
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Affiliation(s)
- Ivo H M van Stokkum
- Institute for Lasers, Life and Biophotonics, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Chanelle C Jumper
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Tia S Lee
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Mykhaylo Myahkostupov
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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