1
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Waly SMA, Benniston AC, Harriman A. Deducing the conformational space for an octa-proline helix. Chem Sci 2024; 15:1657-1671. [PMID: 38303943 PMCID: PMC10829019 DOI: 10.1039/d3sc05287g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/20/2023] [Indexed: 02/03/2024] Open
Abstract
A molecular dyad, PY-P8-PER, comprising a proline octamer sandwiched between pyrene and perylene terminals has been synthesized in order to address the dynamics of electronic energy transfer (EET) along the oligo-proline chain. A simple pyrene-based control compound equipped with a bis-proline attachment serves as a reference for spectroscopic studies. The N-H NMR signal at the terminal pyrene allows distinction between cis and trans amides and, although the crystal structure for the control has the trans conformation, temperature-dependent NMR studies provide clear evidence for trans/cis isomerisation in D6-DMSO. Polar solvents tend to stabilise the trans structure for the pyrene amide group, even for longer oligo-proline units. Circular dichroism shows that the proline spacer for PY-P8-PER exists mainly in the all-trans geometry in methanol. Preferential excitation of the pyrene chromophore is possible at wavelengths in the 320-350 nm range and, for the dyad, is followed by efficacious EET to the perylene emitter. The probability for intramolecular EET, obtained from analysis of steady-state spectroscopic data, is ca. 80-90% in solvents of disparate polarity. Comparison with the Förster critical distance suggests the terminals are ca. 18 Å apart. Time-resolved fluorescence spectroscopy, in conjunction with DFT calculations, indicates the dyad exists as a handful of conformers displaying a narrow range of EET rates. Optimisation of a distributive model allows accurate simulation of the EET dynamics in terms of reasonable structures based on isomerisation of certain amide groups.
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Affiliation(s)
- Sara M A Waly
- Molecular Photonics Laboratory, Bedson Building, School of Natural and Environmental Sciences, Newcastle University Newcastle upon Tyne NE1 7RU UK
| | - Andrew C Benniston
- Molecular Photonics Laboratory, Bedson Building, School of Natural and Environmental Sciences, Newcastle University Newcastle upon Tyne NE1 7RU UK
| | - Anthony Harriman
- Molecular Photonics Laboratory, Bedson Building, School of Natural and Environmental Sciences, Newcastle University Newcastle upon Tyne NE1 7RU UK
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2
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Langhals H, Dietl C. Vibronic Intramolecular Resonant Energy Transfer along More than 5 nm: Synthesis of Dyads for a Re-Examination of the Distance Function of FRET. J Org Chem 2022; 87:9454-9465. [PMID: 35316057 DOI: 10.1021/acs.joc.1c02682] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dyads of chromophores with orthogonal transition moments and sequences of aliphatic cage-structures as spacers were prepared where resonance energy transfer (FRET) proceeded in contrast to Förster's theory even until 58 Å. The distance dependence of the efficiency was re-examined by means of various functions; the commonly used R-6 dependence gave acceptable results, but a slightly larger exponent was more useful for practical applications.
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Affiliation(s)
- Heinz Langhals
- LMU University of Munich, Department of Chemistry, Butenandtstrasee 13, D-81377 Munich, Germany
| | - Christian Dietl
- LMU University of Munich, Department of Chemistry, Butenandtstrasee 13, D-81377 Munich, Germany
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3
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Langhals H, Dietl C, Wiedbrauk S. Balancing from FRET to SET and Further to Photochemistry. Isr J Chem 2021. [DOI: 10.1002/ijch.202100032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Heinz Langhals
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
| | - Christian Dietl
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
| | - Sandra Wiedbrauk
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
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4
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Affiliation(s)
- Heinz Langhals
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
| | - Christian Dietl
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
| | - Peter Mayer
- Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
- X-ray crystal structure analysis Department of Chemistry LMU University of Munich Butenandtstr. 13 D-81377 Munich Germany
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5
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Dong Y, Taddei M, Doria S, Bussotti L, Zhao J, Mazzone G, Di Donato M. Torsion-Induced Nonradiative Relaxation of the Singlet Excited State of meso-Thienyl Bodipy and Charge Separation, Charge Recombination-Induced Intersystem Crossing in Its Compact Electron Donor/Acceptor Dyads. J Phys Chem B 2021; 125:4779-4793. [PMID: 33929843 DOI: 10.1021/acs.jpcb.1c00053] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We prepared a series of meso-thienyl boron-dipyrromethene (Bodipy) derivatives to investigate the spin-orbit charge transfer intersystem crossing (SOCT-ISC). The photophysical properties of the compounds were studied by steady-state and femtosecond/nanosecond transient absorption spectroscopy, as well as density functional theory (DFT) computations. Different from the meso-phenyl Bodipy analogues, the meso-thienyl Bodipy are weakly fluorescent. Based on femtosecond transient absorption and DFT computations, we propose that the torsion of the thienyl group and the distortion of the Bodipy core (19.7 ps) in the S1 state lead to a conical intersection on the potential energy surface as an efficient nonradiative decay channel (408 ps), which is responsible for the observed weak fluorescence as compared to the meso-phenyl analogue. The increased fluorescence quantum yield (from 5.5 to 14.5%) in viscous solvents supports this hypothesis. With the electron donor 4'-hydroxylphenyl moiety attached to the meso-thienyl unit, the fast charge separation (CS, 15.3 ps) and charge recombination (CR, 238 ps) processes outcompete the torsion-induced nonradiative decay and induce fast ISC through the SOCT-ISC mechanism. The triplet quantum yield of the electron donor/acceptor dyad is highly dependent on solvent polarity (ΦT = 1.9-45%), which supports the SOCT-ISC mechanism, and the triplet-state lifetime is up to 247.3 μs. Using the electron donor-acceptor dyad showing SOCT-ISC as a triplet photosensitizer, efficient triplet-triplet annihilation (TTA) upconversion was observed with a quantum yield of up to 6.0%.
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Affiliation(s)
- Yu Dong
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 West Campus, 2 Ling Gong Road, Dalian 116024, P. R. China
| | - Maria Taddei
- LENS (European Laboratory for Non-Linear Spectroscopy), via N. Carrara 1, 50019 Sesto Fiorentino, Firenze, Italy
| | - Sandra Doria
- LENS (European Laboratory for Non-Linear Spectroscopy), via N. Carrara 1, 50019 Sesto Fiorentino, Firenze, Italy.,ICCOM-CNR, via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
| | - Laura Bussotti
- LENS (European Laboratory for Non-Linear Spectroscopy), via N. Carrara 1, 50019 Sesto Fiorentino, Firenze, Italy
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 West Campus, 2 Ling Gong Road, Dalian 116024, P. R. China
| | - Gloria Mazzone
- Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, I-87036 Arcavacata di Rende, Italy
| | - Mariangela Di Donato
- LENS (European Laboratory for Non-Linear Spectroscopy), via N. Carrara 1, 50019 Sesto Fiorentino, Firenze, Italy.,ICCOM-CNR, via Madonna del Piano 10, 50019 Sesto Fiorentino, Firenze, Italy
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6
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Patalag LJ, Hoche J, Holzapfel M, Schmiedel A, Mitric R, Lambert C, Werz DB. Ultrafast Resonance Energy Transfer in Ethylene-Bridged BODIPY Heterooligomers: From Frenkel to Förster Coupling Limit. J Am Chem Soc 2021; 143:7414-7425. [PMID: 33956430 DOI: 10.1021/jacs.1c01279] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A series of distinct BODIPY heterooligomers (dyads, triads, and tetrads) comprising a variable number of typical green BODIPY monomers and a terminal red-emitting styryl-equipped species acting as an energy sink was prepared and subjected to computational and photophysical investigations in solvent media. An ethylene tether between the single monomeric units provides a unique foldameric system, setting the stage for a systematic study of excitation energy transfer processes (EET) on the basis of nonconjugated oscillators. The influence of stabilizing β-ethyl substituents on conformational space and the disorder of site energies and electronic couplings was addressed. In this way both the strong (Frenkel) and the weak (Förster) coupling limit could be accessed within a single system: the Frenkel limit within the strongly coupled homooligomeric green donor subunit and the Förster limit at the terminal heterosubstituted ethylene bridge. Femtosecond transient-absorption spectroscopy combined with mixed quantum-classical dynamic simulations demonstrate the limitations of the Förster resonance energy transfer (FRET) theory and provide a consistent framework to elucidate the trend of increasing relaxation lifetimes at higher homologues, revealing one of the fastest excitation energy transfer processes detected to date with a corresponding lifetime of 39 fs.
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Affiliation(s)
- Lukas J Patalag
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
| | - Joscha Hoche
- Institute of Physical and Theoretical Chemistry, Universität Würzburg, Emil-Fischer-Straße 42, 97074 Würzburg, Germany
| | - Marco Holzapfel
- Institute of Organic Chemistry, Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Alexander Schmiedel
- Institute of Organic Chemistry, Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Roland Mitric
- Institute of Physical and Theoretical Chemistry, Universität Würzburg, Emil-Fischer-Straße 42, 97074 Würzburg, Germany
| | - Christoph Lambert
- Institute of Organic Chemistry, Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Daniel B Werz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany
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7
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Seintis K, Kalis IK, Klikar M, Bureš F, Fakis M. Excitation/detection energy controlled anisotropy dynamics in asymmetrically cyano substituted tri-podal molecules. Phys Chem Chem Phys 2020; 22:16681-16690. [PMID: 32658218 DOI: 10.1039/d0cp01726d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the present work, the photophysical properties of two series of asymmetrical tri-podal molecules are studied, in order to determine the dependence of energy localization/delocalization phenomena on excitation and detection wavelength, by means of steady state, femtosecond time-resolved fluorescence and anisotropy spectroscopy. The molecules bear triphenylamine as an electron donating core and an acetylenic or olefinic π-conjugated bridge. At the periphery, they are substituted by no, one, two or three -CN groups used as electron acceptors. Thus, the compounds with only one or two -CN groups are asymmetrically substituted. As a comparison, the photophysics of their dipolar and quadrupolar analogues is also presented. The steady state absorption spectra of the asymmetrical tri-podal compounds exhibit a broadening and a low energy shoulder due to the splitting of the excited states. The fluorescence spectra are more red-shifted in the tri-podal molecules with a single -CN group, providing the first evidence of its mostly dipolar nature. Time-resolved anisotropy measurements by using different excitation and detection wavelengths provide clear evidence that the asymmetrical tri-podal molecules with one or two -CN groups behave like octupolar molecules upon high-energy excitation (the initial anisotropy is found 0.1-0.15), while upon low-energy excitation they reveal a behavior expected for linear dipolar or V-shaped quadrupolar molecules (the initial anisotropy is very close to 0.4 and 0.17, respectively). The symmetrical tri-podal compounds with no or three cyano groups, exhibit an anisotropy depolarization time of 2.5 ps attributed to energy hopping. The amplitude of this energy hopping component is wavelength dependent and increases as the excitation is shifted towards the long wavelength edge.
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Affiliation(s)
- K Seintis
- Department of Physics, University of Patras, GR-26504, Patras, Greece.
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8
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Langhals H, Walter A. FRET in Dyads with Orthogonal Chromophores and Minimal Spectral Overlap. J Phys Chem A 2020; 124:1554-1560. [DOI: 10.1021/acs.jpca.9b11225] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Heinz Langhals
- LMU University of Munich, Department of Chemistry, Butenandtstr. 13, D-81377 Munich, Germany
| | - Andreas Walter
- LMU University of Munich, Department of Chemistry, Butenandtstr. 13, D-81377 Munich, Germany
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9
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Buck JT, Boudreau AM, DeCarmine A, Wilson RW, Hampsey J, Mani T. Spin-Allowed Transitions Control the Formation of Triplet Excited States in Orthogonal Donor-Acceptor Dyads. Chem 2019. [DOI: 10.1016/j.chempr.2018.10.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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10
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Letrun R, Lang B, Yushchenko O, Wilcken R, Svechkarev D, Kolodieznyi D, Riedle E, Vauthey E. Excited-state dynamics of a molecular dyad with two orthogonally-oriented fluorophores. Phys Chem Chem Phys 2018; 20:30219-30230. [PMID: 30489576 DOI: 10.1039/c8cp05356a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The excited-state dynamics of a T-shaped bichromophoric molecule, consisting of two strong fluorophores, diphenyloxazole and diphenylpyrazoline, directly linked in an orthogonal geometry, was investigated. Despite the weak coupling ensured by this geometry and confirmed by the electronic absorption spectra, this dyad exhibits only weak fluorescence in both apolar and polar solvents, with fluorescence lifetimes ranging from 200 ps in CHX to 10 ps in ACN. Ultrafast spectroscopic measurements reveal that the fluorescence quenching in polar solvents is due to the population of a charge-separated state. In non-polar solvents, this process is energetically not feasible, and a quenching due to an efficient intersystem crossing (ISC) to the triplet manifold is proposed, based on quantum-chemical calculations. This process occurs via the spin-orbit charge-transfer (SOCT) ISC mechanism, which is enabled by the charge-transfer character acquired by the S1 state of the dyad upon structural relaxation and by the orthogonal arrangement of the molecular orbitals involved in the transition. The same mechanism is proposed to explain why the recombination of the charge-separated state is faster in medium than in highly polar solvents, as well as to account for the fast decay of the lowest triplet state to the ground state.
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Affiliation(s)
- Romain Letrun
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland.
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11
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Menger MFSJ, Plasser F, Mennucci B, González L. Surface Hopping within an Exciton Picture. An Electrostatic Embedding Scheme. J Chem Theory Comput 2018; 14:6139-6148. [PMID: 30299941 DOI: 10.1021/acs.jctc.8b00763] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the development and the implementation of an exciton approach that allows ab initio nonadiabatic dynamics simulations of electronic excitation energy transfer in multichromophoric systems. For the dynamics, a trajectory-based strategy is used within the surface hopping formulation. The approach features a consistent hybrid formulation that allows the construction of potential energy surfaces and gradients by combining quantum mechanics and molecular mechanics within an electrostatic embedding scheme. As an application, the study of a molecular dyad consisting of a covalently bound BODIPY moiety and a tetrathiophene group is presented using time-dependent density functional theory (TDDFT). The results obtained with the exciton model are compared to previously performed full TDDFT dynamics of the same system. Our results show excellent agreement with the full TDDFT results, indicating that the couplings that lead to excitation energy transfer (EET) are dominated by Coulomb interaction terms and that charge-transfer states are not necessary to properly describe the nonadiabatic dynamics of the system. The exciton model also reveals ultrafast coherent oscillations of the excitation between the two units in the dyad, which occur during the first 50 fs.
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Affiliation(s)
- Maximilian F S J Menger
- Institute for Theoretical Chemistry, Faculty of Chemistry , University of Vienna , Währingerstrasse 17 , 1090 Vienna , Austria.,Dipartimento di Chimica e Chimica Industriale , University of Pisa , Via G. Moruzzi 13 , 56124 Pisa , Italy
| | - Felix Plasser
- Institute for Theoretical Chemistry, Faculty of Chemistry , University of Vienna , Währingerstrasse 17 , 1090 Vienna , Austria.,Department of Chemistry , Loughborough University , Loughborough LE11 3TU , U.K
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale , University of Pisa , Via G. Moruzzi 13 , 56124 Pisa , Italy
| | - Leticia González
- Institute for Theoretical Chemistry, Faculty of Chemistry , University of Vienna , Währingerstrasse 17 , 1090 Vienna , Austria
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12
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Ziessel R, Stachelek P, Harriman A, Hedley GJ, Roland T, Ruseckas A, Samuel IDW. Ultrafast Through-Space Electronic Energy Transfer in Molecular Dyads Built around Dynamic Spacer Units. J Phys Chem A 2018; 122:4437-4447. [DOI: 10.1021/acs.jpca.8b02415] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Raymond Ziessel
- Molecular Photonics Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Patrycja Stachelek
- Molecular Photonics Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Anthony Harriman
- Molecular Photonics Laboratory, School of Chemistry, Bedson Building, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Gordon J. Hedley
- Organic Semiconductor Centre, SUPA, School of Physics & Astronomy, Physical Science Building, University of St. Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Thomas Roland
- Organic Semiconductor Centre, SUPA, School of Physics & Astronomy, Physical Science Building, University of St. Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Arvydas Ruseckas
- Organic Semiconductor Centre, SUPA, School of Physics & Astronomy, Physical Science Building, University of St. Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
| | - Ifor D. W. Samuel
- Organic Semiconductor Centre, SUPA, School of Physics & Astronomy, Physical Science Building, University of St. Andrews, North Haugh, St Andrews KY16 9SS, United Kingdom
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13
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Abstract
The breaking of molecular symmetry through photoexcitation is a ubiquitous but rather elusive process, which, for example, controls the microscopic efficiency of light harvesting in molecular aggregates. A molecular excitation within a π-conjugated segment will self-localize due to strong coupling to molecular vibrations, locally changing bond alternation in a process which is fundamentally nondeterministic. Probing such symmetry breaking usually relies on polarization-resolved fluorescence, which is most powerful on the level of single molecules. Here, we explore symmetry breaking by designing a large, asymmetric acceptor-donor-acceptor (A1-D-A2) complex 10 nm in length, where excitation energy can flow from the donor, a π-conjugated oligomer, to either one of the two boron-dipyrromethene (bodipy) dye acceptors of different color. Fluorescence correlation spectroscopy (FCS) reveals a nondeterministic switching between the energy-transfer pathways from the oligomer to the two acceptor groups on the submillisecond timescale. We conclude that excitation energy transfer, and light harvesting in general, are fundamentally nondeterministic processes, which can be strongly perturbed by external stimuli. A simple demonstration of the relation between exciton localization within the extended π-system and energy transfer to the endcap is given by considering the selectivity of endcap emission through the polarization of the excitation light in triads with bent oligomer backbones. Bending leads to increased localization so that the molecule acquires bichromophoric characteristics in terms of its fluorescence photon statistics.
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14
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Fakis M, Beckwith JS, Seintis K, Martinou E, Nançoz C, Karakostas N, Petsalakis I, Pistolis G, Vauthey E. Energy transfer and charge separation dynamics in photoexcited pyrene-bodipy molecular dyads. Phys Chem Chem Phys 2018; 20:837-849. [PMID: 29230451 DOI: 10.1039/c7cp06914f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The photophysical properties of two pyrene-bodipy molecular dyads, composed of a phenyl-pyrene (Py-Ph) linked to the meso position of a bodipy (BD) molecule with either H-atoms (BD1) or ethyl groups (BD2) at the 2,6 positions, are investigated by stationary, nanosecond and femtosecond spectroscopy. The properties of these dyads (Py-Ph-BD1 and Py-Ph-BD2) are compared to those of their constituent chromophores in two solvents namely 1,2-dichloroethane (DCE) and acetonitrile (ACN). Stationary spectroscopy reveals a weak coupling among the subunits in both dyads. Excitation of the pyrene (Py) subunit leads to emission that is totally governed by the BD subunits in both dyads pointing to excitation energy transfer (EET) from the Py to BD chromophore. Femtosecond fluorescence and transient absorption spectroscopy reveal that EET takes place within 0.3-0.5 ps and is mostly independent of the solvent and the type of the BD subunit. The EET lifetime is in reasonable agreement with that predicted by Förster theory. After EET has taken place, Py-Ph-BD1 in DCE and Py-Ph-BD2 in both solvents decay mainly radiatively to the ground state with 3.5-5.0 ns lifetimes which are similar to those of the individual BD chromophores. However, the excited state of Py-Ph-BD1 in ACN is quenched having a lifetime of 1 ns. This points to the opening of an additional non-radiative channel of the excited state of Py-Ph-BD1 in this solvent, most probably charge separation (CS). Target analysis of the TA spectra has shown that the CS follows inverted kinetics and is substantially slower than the recombination of the charge-separated state. Occurrence of CS with Py-Ph-BD1 in ACN is also supported by energetic considerations. The above results indicate that only a small change in the structure of the BD units incorporated in the dyads significantly affects the excited state dynamics leading either to a dyad with long lifetime and high fluorescence quantum yield or to a dyad with ability to undergo CS.
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Affiliation(s)
- M Fakis
- Department of Physics, University of Patras, GR-26504, Patras, Greece.
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15
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He X, Benniston AC, Lemmetyinen H, Tkachenko NV. Charge Shift/Recombination and Triplet Formation in a Molecular Dyad based on a Borondipyrromethene (Bodipy) and an Expanded Acridinium Cation. CHEMPHOTOCHEM 2018. [DOI: 10.1002/cptc.201700184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiaoyan He
- Molecular Photonics Laboratory, Chemistry-School of Natural & Environmental Sciences; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Andrew C. Benniston
- Molecular Photonics Laboratory, Chemistry-School of Natural & Environmental Sciences; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Helge Lemmetyinen
- Laboratory of Chemistry & Bioengineering; Tampere University of Technology, PO Box 541; Tampere FIN-33101 Finland
| | - Nikolai V. Tkachenko
- Laboratory of Chemistry & Bioengineering; Tampere University of Technology, PO Box 541; Tampere FIN-33101 Finland
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16
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Wiebeler C, Plasser F, Hedley GJ, Ruseckas A, Samuel IDW, Schumacher S. Ultrafast Electronic Energy Transfer in an Orthogonal Molecular Dyad. J Phys Chem Lett 2017; 8:1086-1092. [PMID: 28206765 DOI: 10.1021/acs.jpclett.7b00089] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Understanding electronic energy transfer (EET) is an important ingredient in the development of artificial photosynthetic systems and photovoltaic technologies. Although EET is at the heart of these applications and crucially influences their light-harvesting efficiency, the nature of EET over short distances for covalently bound donor and acceptor units is often not well understood. Here we investigate EET in an orthogonal molecular dyad (BODT4), in which simple models fail to explain the very origin of EET. On the basis of nonadiabatic ab initio molecular dynamics calculations and ultrafast fluorescence experiments, we gain detailed microscopic insights into the ultrafast electrovibrational dynamics following photoexcitation. Our analysis offers molecular-level insights into these processes and reveals that it takes place on time scales ≲100 fs and occurs through an intermediate charge-transfer state.
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Affiliation(s)
- Christian Wiebeler
- Physics Department and Center for Optoelectronics and Photonics Paderborn (CeOPP), Universität Paderborn , Warburger Strasse 100, 33098 Paderborn, Germany
| | - Felix Plasser
- Institute for Theoretical Chemistry, Faculty of Chemistry, University of Vienna , Währingerstr. 17, 1090 Vienna, Austria
| | - Gordon J Hedley
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St. Andrews , North Haugh, St. Andrews, Fife KY16 9SS, United Kingdom
- Institut für Experimentelle und Angewandte Physik, Universität Regensburg , Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Arvydas Ruseckas
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St. Andrews , North Haugh, St. Andrews, Fife KY16 9SS, United Kingdom
| | - Ifor D W Samuel
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St. Andrews , North Haugh, St. Andrews, Fife KY16 9SS, United Kingdom
| | - Stefan Schumacher
- Physics Department and Center for Optoelectronics and Photonics Paderborn (CeOPP), Universität Paderborn , Warburger Strasse 100, 33098 Paderborn, Germany
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17
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Meineke DNH, Bossi ML, Ta H, Belov VN, Hell SW. Bichromophoric Compounds with Orthogonally and Parallelly Arranged Chromophores Separated by Rigid Spacers. Chemistry 2017; 23:2469-2475. [PMID: 27922726 DOI: 10.1002/chem.201605587] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Dirk N. H. Meineke
- NanoBiophotonics Department; Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 37077 Göttingen Germany
| | - Mariano L. Bossi
- NanoBiophotonics Department; Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 37077 Göttingen Germany
| | - Haisen Ta
- NanoBiophotonics Department; Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 37077 Göttingen Germany
| | - Vladimir N. Belov
- NanoBiophotonics Department; Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 37077 Göttingen Germany
| | - Stefan W. Hell
- NanoBiophotonics Department; Max Planck Institute for Biophysical Chemistry; Am Fassberg 11 37077 Göttingen Germany
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Al-Aqar R, Atahan A, Benniston AC, Perks T, Waddell PG, Harriman A. Exciton Migration and Surface Trapping for a Photonic Crystal Displaying Charge-Recombination Fluorescence. Chemistry 2016; 22:15420-15429. [DOI: 10.1002/chem.201602155] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Roza Al-Aqar
- Molecular Photonics Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Alparslan Atahan
- Molecular Photonics Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
- Department of Polymer Engineering; Faculty of Technology; Duzce University; Duzce 81620 Turkey
| | - Andrew C. Benniston
- Molecular Photonics Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Thomas Perks
- Molecular Photonics Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Paul G. Waddell
- Crystallography Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Anthony Harriman
- Molecular Photonics Laboratory; School of Chemistry; Bedson Building; Newcastle University; Newcastle upon Tyne NE1 7RU UK
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