1
|
Huang Y, Qiu Y, Young RM, Schatz GC, Krzyaniak MD, Wasielewski MR. Identifying Sources of Entanglement Loss in Photodriven Molecular Electron Spin Teleportation. J Am Chem Soc 2024; 146:20133-20140. [PMID: 38995837 DOI: 10.1021/jacs.4c04393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2024]
Abstract
We report on an electron donor-electron acceptor-stable radical (D-A-R•) molecule in which an electron spin state first prepared on R• is followed by photogeneration of an entangled singlet 1[D•+-A•-] spin pair to produce D•+-A•--R•. Since the A•- and R• spins within D•+-A•--R• are uncorrelated, spin teleportation from R• to D•+ occurs with a maximal 25% efficiency only for the singlet pair 1(A•--R•) by spin-allowed electron transfer from A•- to R•. However, since 1[D•+-A•-] is sufficiently long-lived, coherent spin mixing involving the unreactive 3(A•--R•) population affects entanglement and teleportation within D•+-A•--R•. Pulse electron paramagnetic resonance experiments show a direct correlation between electron spin flip-flops and entanglement loss, providing information for designing molecular materials to serve as nanoscale quantum device interconnects.
Collapse
|
2
|
De Biasi F, Hope MA, Qiu Y, Brown PJ, Visegrádi M, Ouari O, Wasielewski MR, Emsley L. Magic Angle Spinning Solid-State 13C Photochemically Induced Dynamic Nuclear Polarization by a Synthetic Donor-Chromophore-Acceptor System at 9.4 T. J Phys Chem Lett 2024; 15:5488-5494. [PMID: 38748557 PMCID: PMC11129313 DOI: 10.1021/acs.jpclett.4c01121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/06/2024] [Accepted: 05/10/2024] [Indexed: 05/24/2024]
Abstract
Solid-state photochemically induced dynamic nuclear polarization (photo-CIDNP) is a nuclear magnetic resonance spectroscopy technique in which nuclear spin hyperpolarization is generated upon optical irradiation of an appropriate donor-acceptor system. Until now, solid-state photo-CIDNP at high magnetic fields has been observed only in photosynthetic reaction centers and flavoproteins. In the present work, we show that the effect is not limited to such biomolecular samples, and solid-state 13C photo-CIDNP can be observed at 9.4 T under magic angle spinning using a frozen solution of a synthetic molecular system dissolved in an organic solvent. Signal enhancements for the source molecule larger than a factor of 2300 are obtained. In addition, we show that bulk 13C hyperpolarization of the solvent can be generated via spontaneous 13C-13C spin diffusion at natural abundance.
Collapse
Affiliation(s)
- Federico De Biasi
- Institut
des Sciences et Ingenierie Chimiques, École
Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Michael A. Hope
- Institut
des Sciences et Ingenierie Chimiques, École
Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Yunfan Qiu
- Department
of Chemistry, Center for Molecular Quantum Transduction, Paula M.
Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Paige J. Brown
- Department
of Chemistry, Center for Molecular Quantum Transduction, Paula M.
Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Máté Visegrádi
- Institut
des Sciences et Ingenierie Chimiques, École
Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Olivier Ouari
- Aix-Marseille
University, Centre National de la Recherche Scientifique (CNRS), Institut
de Chimie Radicalaire, 13013 Marseille, France
| | - Michael R. Wasielewski
- Department
of Chemistry, Center for Molecular Quantum Transduction, Paula M.
Trienens Institute for Sustainability and Energy, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Lyndon Emsley
- Institut
des Sciences et Ingenierie Chimiques, École
Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
3
|
De Biasi F, Hope MA, Avalos CE, Karthikeyan G, Casano G, Mishra A, Badoni S, Stevanato G, Kubicki DJ, Milani J, Ansermet JP, Rossini AJ, Lelli M, Ouari O, Emsley L. Optically Enhanced Solid-State 1H NMR Spectroscopy. J Am Chem Soc 2023. [PMID: 37366803 DOI: 10.1021/jacs.3c03937] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Low sensitivity is the primary limitation to extending nuclear magnetic resonance (NMR) techniques to more advanced chemical and structural studies. Photochemically induced dynamic nuclear polarization (photo-CIDNP) is an NMR hyperpolarization technique where light is used to excite a suitable donor-acceptor system, creating a spin-correlated radical pair whose evolution drives nuclear hyperpolarization. Systems that exhibit photo-CIDNP in solids are not common, and this effect has, up to now, only been observed for 13C and 15N nuclei. However, the low gyromagnetic ratio and natural abundance of these nuclei trap the local hyperpolarization in the vicinity of the chromophore and limit the utility for bulk hyperpolarization. Here, we report the first example of optically enhanced solid-state 1H NMR spectroscopy in the high-field regime. This is achieved via photo-CIDNP of a donor-chromophore-acceptor molecule in a frozen solution at 0.3 T and 85 K, where spontaneous spin diffusion among the abundant strongly coupled 1H nuclei relays polarization through the whole sample, yielding a 16-fold bulk 1H signal enhancement under continuous laser irradiation at 450 nm. These findings enable a new strategy for hyperpolarized NMR beyond the current limits of conventional microwave-driven DNP.
Collapse
Affiliation(s)
- Federico De Biasi
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Michael A Hope
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Claudia E Avalos
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ganesan Karthikeyan
- Institute of Radical Chemistry, Aix-Marseille University, CNRS, ICR, 13013 Marseille, France
| | - Gilles Casano
- Institute of Radical Chemistry, Aix-Marseille University, CNRS, ICR, 13013 Marseille, France
| | - Aditya Mishra
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Saumya Badoni
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Gabriele Stevanato
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dominik J Kubicki
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jonas Milani
- Institut de Physique, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jean-Philippe Ansermet
- Institut de Physique, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Aaron J Rossini
- U.S. Department of Energy, Ames Laboratory, Ames, Iowa 50011, United States
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - Moreno Lelli
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, 50019 Sesto Fiorentino, Italy
- Consorzio Interuniversitario Risonanze Magnetiche delle Metalloproteine Paramagnetiche (CIRMMP), 50019 Sesto Fiorentino, Italy
| | - Olivier Ouari
- Institute of Radical Chemistry, Aix-Marseille University, CNRS, ICR, 13013 Marseille, France
| | - Lyndon Emsley
- Institut des Sciences et Ingenierie Chimiques, École Polytechnique Fedérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
4
|
Mao H, Pažėra GJ, Young RM, Krzyaniak MD, Wasielewski MR. Quantum Gate Operations on a Spectrally Addressable Photogenerated Molecular Electron Spin-Qubit Pair. J Am Chem Soc 2023; 145:6585-6593. [PMID: 36913602 DOI: 10.1021/jacs.3c01243] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
Sub-nanosecond photodriven electron transfer from a molecular donor to an acceptor can be used to generate a radical pair (RP) having two entangled electron spins in a well-defined pure initial singlet quantum state to serve as a spin-qubit pair (SQP). Achieving good spin-qubit addressability is challenging because many organic radical ions have large hyperfine couplings (HFCs) in addition to significant g-anisotropy, which results in significant spectral overlap. Moreover, using radicals with g-factors that deviate significantly from that of the free electron results in difficulty generating microwave pulses with sufficiently large bandwidths to manipulate the two spins either simultaneously or selectively as is necessary to implement the controlled-NOT (CNOT) quantum gate essential for quantum algorithms. Here, we address these issues by using a covalently linked donor-acceptor(1)-acceptor(2) (D-A1-A2) molecule with significantly reduced HFCs that uses fully deuterated peri-xanthenoxanthene (PXX) as D, naphthalenemonoimide (NMI) as A1, and a C60 derivative as A2. Selective photoexcitation of PXX within PXX-d9-NMI-C60 results in sub-nanosecond, two-step electron transfer to generate the long-lived PXX•+-d9-NMI-C60•- SQP. Alignment of PXX•+-d9-NMI-C60•- in the nematic liquid crystal 4-cyano-4'-(n-pentyl)biphenyl (5CB) at cryogenic temperatures results in well-resolved, narrow resonances for each electron spin. We demonstrate both single-qubit gate and two-qubit CNOT gate operations using both selective and nonselective Gaussian-shaped microwave pulses and broadband spectral detection of the spin states following the gate operations.
Collapse
Affiliation(s)
- Haochuan Mao
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Gediminas J Pažėra
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3QZ, U.K
| | - Ryan M Young
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D Krzyaniak
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| |
Collapse
|
5
|
Ye K, Cao L, van Raamsdonk DME, Wang Z, Zhao J, Escudero D, Jacquemin D. Naphthalimide-phenothiazine dyads: effect of conformational flexibility and matching of the energy of the charge-transfer state and the localized triplet excited state on the thermally activated delayed fluorescence. Beilstein J Org Chem 2022; 18:1435-1453. [PMID: 36300011 PMCID: PMC9577389 DOI: 10.3762/bjoc.18.149] [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: 04/14/2022] [Accepted: 09/26/2022] [Indexed: 11/23/2022] Open
Abstract
In order to investigate the joint influence of the conformation flexibility and the matching of the energies of the charge-transfer (CT) and the localized triplet excited (3LE) states on the thermally activated delayed fluorescence (TADF) in electron donor–acceptor molecules, a series of compact electron donor–acceptor dyads and a triad were prepared, with naphthalimide (NI) as electron acceptor and phenothiazine (PTZ) as electron donor. The NI and PTZ moieties are either directly connected at the 3-position of NI and the N-position of the PTZ moiety via a C–N single bond, or they are linked through a phenyl group. The tuning of the energy order of the CT and LE states is achieved by oxidation of the PTZ unit into the corresponding sulfoxide, whereas conformation restriction is imposed by introducing ortho-methyl substituents on the phenyl linker, so that the coupling magnitude between the CT and the 3LE states can be controlled. The singlet oxygen quantum yield (ΦΔ) of NI-PTZ is moderate in n-hexane (HEX, ΦΔ = 19%). TADF was observed for the dyads, the biexponential luminescence lifetime are 16.0 ns (99.9%)/14.4 μs (0.1%) for the dyad and 7.2 ns (99.6%)/2.0 μs (0.4%) for the triad. Triplet state was observed in the nanosecond transient absorption spectra with lifetimes in the 4–48 μs range. Computational investigations show that the orthogonal electron donor–acceptor molecular structure is beneficial for TADF. These calculations indicate small energetic difference between the 3LE and 3CT states, which are helpful for interpreting the ns-TA spectra and the origins of TADF in NI-PTZ, which is ultimately due to the small energetic difference between the 3LE and 3CT states. Conversely, NI-PTZ-O, which has a higher CT state and bears a much more stabilized 3LE state, does not show TADF.
Collapse
Affiliation(s)
- Kaiyue Ye
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Liyuan Cao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | | | - Zhijia Wang
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, P. R. China
| | | | - Denis Jacquemin
- Nantes Université, CNRS, CEISAM UMR-6230, Nantes F-44000, France
| |
Collapse
|
6
|
Chen X, Sukhanov AA, Yan Y, Bese D, Bese C, Zhao J, Voronkova VK, Barbon A, Yaglioglu HG. Long‐Lived Charge‐Transfer State in Spiro Compact Electron Donor–Acceptor Dyads Based on Pyromellitimide‐Derived Rhodamine: Charge Transfer Dynamics and Electron Spin Polarization. Angew Chem Int Ed Engl 2022; 61:e202203758. [PMID: 35384206 PMCID: PMC9543469 DOI: 10.1002/anie.202203758] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Indexed: 12/16/2022]
Affiliation(s)
- Xi Chen
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Andrey A. Sukhanov
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Yuxin Yan
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Damla Bese
- Department of Engineering Physics Faculty of Engineering Ankara University 06100, Beşevler Ankara Turkey
| | - Cagri Bese
- Department of Physics Engineering Hacettepe University 06800 Beytepe Ankara Turkey
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Violeta K. Voronkova
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Antonio Barbon
- Dipartimento di Scienze Chimiche Università degli Studi di Padova 35131 Padova Italy
| | - Halime Gul Yaglioglu
- Department of Engineering Physics Faculty of Engineering Ankara University 06100, Beşevler Ankara Turkey
| |
Collapse
|
7
|
Chen X, Sukhanov AA, Yan Y, Bese D, Bese C, Zhao J, Voronkova VK, Barbon A, Yaglioglu HG. Long‐Lived Charge‐Transfer State in Spiro Compact Electron Donor–Acceptor Dyads Based on Pyromellitimide‐Derived Rhodamine: Charge Transfer Dynamics and Electron Spin Polarization. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202203758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Xi Chen
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Andrey A. Sukhanov
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Yuxin Yan
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Damla Bese
- Department of Engineering Physics Faculty of Engineering Ankara University 06100, Beşevler Ankara Turkey
| | - Cagri Bese
- Department of Physics Engineering Hacettepe University 06800 Beytepe Ankara Turkey
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology 2 Ling Gong Road Dalian 116024 P. R. China
| | - Violeta K. Voronkova
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Antonio Barbon
- Dipartimento di Scienze Chimiche Università degli Studi di Padova 35131 Padova Italy
| | - Halime Gul Yaglioglu
- Department of Engineering Physics Faculty of Engineering Ankara University 06100, Beşevler Ankara Turkey
| |
Collapse
|
8
|
Kirk ML, Shultz DA, Hewitt P, van der Est A. Excited State Exchange Control of Photoinduced Electron Spin Polarization in Electronic Ground States. J Phys Chem Lett 2022; 13:872-878. [PMID: 35045702 DOI: 10.1021/acs.jpclett.1c03491] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Ground-state electron spin polarization (ESP) is generated in radical elaborated (bpy)Pt(CAT-NN) and (bpy)Pt(CAT-p-Me2PhMe2-NN) (bpy = 5,5'-di-tert-butyl-2,2'-bipyridine, CAT = 3-tert-butylcatecholate, p-Ph = para-phenylene, NN = nitronylnitroxide). Photoexcitation produces an exchange-coupled, three-spin, charge-separated doublet 2S1 (S = chromophore excited spin singlet configuration) excited state that rapidly decays to a 2T1 (T = chromophore excited spin triplet configuration) excited state. The SQ-bridge-NN bond torsions affect the magnitude of the excited state exchange interaction (JSQ-NN), which determines the 2T1-4T1 energy gap. Ground state ESP is dependent on the magnitude of JSQ-NN, and we postulate that this results from differences in 2T1 and 4T1 state mixing. Mechanisms that lead to the rapid transfer of the excited state ESP to the ground state are discussed. Although subnanosecond 2T1 state lifetimes are measured optically in solution, the ground state ESP decays very slowly at 20 K and is observable for more than a millisecond.
Collapse
Affiliation(s)
- Martin L Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
- The Center for High Technology Materials, The University of New Mexico, Albuquerque, New Mexico 87106, United States
| | - David A Shultz
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Patrick Hewitt
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Art van der Est
- Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| |
Collapse
|
9
|
Kirk ML, Shultz DA, Hewitt P, Stasiw DE, Chen J, van der Est A. Chromophore-radical excited state antiferromagnetic exchange controls the sign of photoinduced ground state spin polarization. Chem Sci 2021; 12:13704-13710. [PMID: 34760154 PMCID: PMC8549796 DOI: 10.1039/d1sc02965g] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/01/2021] [Indexed: 11/21/2022] Open
Abstract
A change in the sign of the ground-state electron spin polarization (ESP) is reported in complexes where an organic radical (nitronylnitroxide, NN) is covalently attached to a donor-acceptor chromophore via two different meta-phenylene bridges in (bpy)Pt(CAT-m-Ph-NN) (mPh-Pt) and (bpy)Pt(CAT-6-Me-m-Ph-NN) (6-Me-mPh-Pt) (bpy = 5,5'-di-tert-butyl-2,2'-bipyridine, CAT = 3-tert-butylcatecholate, m-Ph = meta-phenylene). These molecules represent a new class of chromophores that can be photoexcited with visible light to produce an initial exchange-coupled, 3-spin (bpy˙-, CAT+˙ = semiquinone (SQ), and NN), charge-separated doublet 2S1 (S = chromophore excited spin singlet configuration) excited state. Following excitation, the 2S1 state rapidly decays to the ground state by magnetic exchange-mediated enhanced internal conversion via the 2T1 (T = chromophore excited spin triplet configuration) state. This process generates emissive ground state ESP in 6-Me-mPh-Pt while for mPh-Pt the ESP is absorptive. It is proposed that the emissive polarization in 6-Me-mPh-Pt results from zero-field splitting induced transitions between the chromophoric 2T1 and 4T1 states, whereas predominant spin-orbit induced transitions between 2T1 and low-energy NN-based states give rise to the absorptive polarization observed for mPh-Pt. The difference in the sign of the ESP for these molecules is consistent with a smaller excited state 2T1 - 4T1 gap for 6-Me-mPh-Pt that derives from steric interactions with the 6-methyl group. These steric interactions reduce the excited state pairwise SQ-NN exchange coupling compared to that in mPh-Pt.
Collapse
Affiliation(s)
- Martin L Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico MSC03 2060, 1 University of New Mexico Albuquerque NM 87131-0001 USA
| | - David A Shultz
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - Patrick Hewitt
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - Daniel E Stasiw
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - Ju Chen
- Department of Chemistry and Chemical Biology, The University of New Mexico MSC03 2060, 1 University of New Mexico Albuquerque NM 87131-0001 USA
| | - Art van der Est
- Department of Chemistry, Brock University St. Catharines Ontario Canada L2S 3A1
| |
Collapse
|
10
|
Harvey SM, Wasielewski MR. Photogenerated Spin-Correlated Radical Pairs: From Photosynthetic Energy Transduction to Quantum Information Science. J Am Chem Soc 2021; 143:15508-15529. [PMID: 34533930 DOI: 10.1021/jacs.1c07706] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
More than a half century ago, the NMR spectra of diamagnetic products resulting from radical pair reactions were observed to have strongly enhanced absorptive and emissive resonances. At the same time, photogenerated radical pairs were discovered to exhibit unusual electron paramagnetic resonance spectra that also had such resonances. These non-Boltzmann, spin-polarized spectra were observed in both chemical systems as well as in photosynthetic reaction center proteins following photodriven charge separation. Subsequent studies of these phenomena led to a variety of chemical electron donor-acceptor model systems that provided a broad understanding of the spin dynamics responsible for these spectra. When the distance between the two radicals is restricted, these observations result from the formation of spin-correlated radical pairs (SCRPs) in which the spin-spin exchange and dipolar interactions between the two unpaired spins play an important role in the spin dynamics. Early on, it was recognized that SCRPs photogenerated by ultrafast electron transfer are entangled spin pairs created in a well-defined spin state. These SCRPs can serve as spin qubit pairs (SQPs), whose spin dynamics can be manipulated to study a wide variety of quantum phenomena intrinsic to the field of quantum information science. This Perspective highlights the role of SCRPs as SQPs, gives examples of possible quantum manipulations using SQPs, and provides some thoughts on future directions.
Collapse
Affiliation(s)
- Samantha M Harvey
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| |
Collapse
|
11
|
Mao H, Young RM, Krzyaniak MD, Wasielewski MR. Controlling the Dynamics of Three Electron Spin Qubits in a Donor-Acceptor-Radical Molecule Using Dielectric Environment Changes. J Phys Chem Lett 2021; 12:2213-2218. [PMID: 33630591 DOI: 10.1021/acs.jpclett.1c00077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Photogenerated entangled electron spin pairs provide a versatile source of molecular qubits. Here, we examine the spin-dependent dynamics of a covalent donor-acceptor-radical molecule, D-A-R•, where the donor chromophore (D) is peri-xanthenoxanthene (PXX), the acceptor (A) is pyromellitimide (PI), and the radical (R•) is α,γ-bisdiphenylene-β-phenylallyl (BDPA). Selective photoexcitation of D within D-A-R• in butyronitrile/propionitrile at 140 K and butyronitrile at 105 K results in the spin-selective reactions D-A-R• → D•+-1(A•--R•) and D•+-3(A•--R•). Subsequently, at 140 K, D•+-1(A•--R•) → D•+-A-R-, whereas D•+-3(A•--R•) → D-A-R•. In contrast, at 105 K, D•+-3(A•--R•) → 3*D-A-R• and D-A-R•. Time-resolved EPR spectroscopy shows that 3*D-A-R• is highly spin-polarized, where the ms = ±1/2 spin sublevels of the doublet-quartet manifolds are selectively populated. These results demonstrate dielectric environment control over different spin states in the same molecule.
Collapse
Affiliation(s)
- Haochuan Mao
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M Young
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D Krzyaniak
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| |
Collapse
|
12
|
Grzegorzek N, Mao H, Michel P, Junge MJ, Lorenzo ER, Young RM, Krzyaniak MD, Wasielewski MR, Chernick ET. Metalated Porphyrin Stable Free Radicals: Exploration of Electron Spin Communication and Dynamics. J Phys Chem A 2020; 124:6168-6176. [DOI: 10.1021/acs.jpca.0c03176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Norbert Grzegorzek
- Institute für Organische Chemie, University of Tübingen, Auf Der Morgenstelle 18, A-Bau, Tübingen 72076, Germany
| | - Haochuan Mao
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Patrick Michel
- Institute für Organische Chemie, University of Tübingen, Auf Der Morgenstelle 18, A-Bau, Tübingen 72076, Germany
| | - Marc J. Junge
- Institute für Organische Chemie, University of Tübingen, Auf Der Morgenstelle 18, A-Bau, Tübingen 72076, Germany
| | - Emmaline R. Lorenzo
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D. Krzyaniak
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Erin T. Chernick
- Institute für Organische Chemie, University of Tübingen, Auf Der Morgenstelle 18, A-Bau, Tübingen 72076, Germany
| |
Collapse
|
13
|
Teki Y. Excited‐State Dynamics of Non‐Luminescent and Luminescent π‐Radicals. Chemistry 2019; 26:980-996. [DOI: 10.1002/chem.201903444] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/28/2019] [Indexed: 11/11/2022]
Affiliation(s)
- Yoshio Teki
- Division of Molecular Materials ScienceGraduate School of ScienceOsaka City University 3-3-138 Sugimoto Sumiyoshi-ku Osaka 558-8585 Japan
| |
Collapse
|
14
|
Tichnell CR, Daley DR, Stein BW, Shultz DA, Kirk ML, Danilov EO. Wave Function Control of Charge-Separated Excited-State Lifetimes. J Am Chem Soc 2019; 141:3986-3992. [DOI: 10.1021/jacs.8b13011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Christopher R. Tichnell
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - David R. Daley
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Benjamin W. Stein
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - David A. Shultz
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Martin L. Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
| | - Evgeny O. Danilov
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| |
Collapse
|
15
|
Horwitz NE, Phelan BT, Nelson JN, Mauck CM, Krzyaniak MD, Wasielewski MR. Spin Polarization Transfer from a Photogenerated Radical Ion Pair to a Stable Radical Controlled by Charge Recombination. J Phys Chem A 2017; 121:4455-4463. [DOI: 10.1021/acs.jpca.7b03468] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Noah E. Horwitz
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Brian T. Phelan
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Jordan N. Nelson
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Catherine M. Mauck
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D. Krzyaniak
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research
(ANSER) Center, and §Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| |
Collapse
|
16
|
Horwitz NE, Phelan BT, Nelson JN, Krzyaniak MD, Wasielewski MR. Picosecond Control of Photogenerated Radical Pair Lifetimes Using a Stable Third Radical. J Phys Chem A 2016; 120:2841-53. [PMID: 27108738 DOI: 10.1021/acs.jpca.6b02621] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photoinduced electron transfer reactions in organic donor-acceptor systems leading to long-lived radical ion pairs (RPs) have attracted broad interest for their potential applications in fields as diverse as solar energy conversion and spintronics. We present the photophysics and spin dynamics of an electron donor - electron acceptor - stable radical system consisting of a meta-phenylenediamine (mPD) donor covalently linked to a 4-aminonaphthalene-1,8-dicarboximide (ANI) electron-accepting chromophore as well as an α,γ-bisdiphenylene-β-phenylallyl (BDPA) stable radical. Selective photoexcitation of ANI produces the BDPA-mPD(+•)-ANI(-•) triradical in which the mPD(+•)-ANI(-•) RP spins are strongly exchange coupled. The presence of BDPA is found to greatly increase the RP intersystem crossing rate from the initially photogenerated BDPA-(1)(mPD(+•)-ANI(-•)) to BDPA-(3)(mPD(+•)-ANI(-•)), resulting in accelerated RP recombination via the triplet channel to produce BDPA-mPD-(3*)ANI as compared to a reference molecule lacking the BDPA radical. The RP recombination rates observed are much faster than those previously reported for weakly coupled triradical systems. Time-resolved EPR spectroscopy shows that this process is also associated with strong spin polarization of the stable radical. Overall, these results show that RP intersystem crossing rates can be strongly influenced by stable radicals nearby strongly coupled RP systems, making it possible to use a third spin to control RP lifetimes down to a picosecond time scale.
Collapse
Affiliation(s)
- Noah E Horwitz
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Brian T Phelan
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Jordan N Nelson
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Matthew D Krzyaniak
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University , Evanston, Illinois 60208-3113, United States
| |
Collapse
|
17
|
|
18
|
Takahashi H, Iwama M, Akai N, Shibuya K, Kawai A. Pulsed EPR study on large dynamic electron polarisation created in the quenching of photo-excited xanthene dyes by nitroxide radicals in aqueous solutions. Mol Phys 2013. [DOI: 10.1080/00268976.2013.827255] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
19
|
Colvin MT, Carmieli R, Miura T, Richert S, Gardner DM, Smeigh AL, Dyar SM, Conron SM, Ratner MA, Wasielewski MR. Electron Spin Polarization Transfer from Photogenerated Spin-Correlated Radical Pairs to a Stable Radical Observer Spin. J Phys Chem A 2013; 117:5314-25. [DOI: 10.1021/jp4045012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Michael T. Colvin
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Raanan Carmieli
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Tomoaki Miura
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Sabine Richert
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Daniel M. Gardner
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Amanda L. Smeigh
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Scott M. Dyar
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Sarah M. Conron
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Mark A. Ratner
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry and Argonne-Northwestern Solar
Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| |
Collapse
|
20
|
Kanemoto K, Fukunaga A, Yasui M, Kosumi D, Hashimoto H, Tamekuni H, Kawahara Y, Takemoto Y, Takeuchi J, Miura Y, Teki Y. Ultrafast photoexcitation dynamics of π-conjugated bodipy-anthracene-radical triad system. RSC Adv 2012. [DOI: 10.1039/c2ra20473h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
21
|
Kondratenko M, Moiseev AG, Perepichka DF. New stable donor–acceptor dyads for molecular electronics. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm02545c] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
22
|
Colvin MT, Giacobbe EM, Cohen B, Miura T, Scott AM, Wasielewski MR. Competitive Electron Transfer and Enhanced Intersystem Crossing in Photoexcited Covalent TEMPO−Perylene-3,4:9,10-bis(dicarboximide) Dyads: Unusual Spin Polarization Resulting from the Radical−Triplet Interaction. J Phys Chem A 2010; 114:1741-8. [DOI: 10.1021/jp909212c] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Michael T. Colvin
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Emilie M. Giacobbe
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Boiko Cohen
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Tomoaki Miura
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Amy M. Scott
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael R. Wasielewski
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| |
Collapse
|
23
|
Matsumoto I, Ciofini I, Lainé P, Teki Y. Intramolecular Spin Alignment within Mono-Oxidized and Photoexcited Anthracene-Based π Radicals as Prototypical Photomagnetic Molecular Devices: Relationships Between Electrochemical, Photophysical, and Photochemical Control Pathways. Chemistry 2009; 15:11210-20. [DOI: 10.1002/chem.200900350] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
24
|
Giacobbe EM, Mi Q, Colvin MT, Cohen B, Ramanan C, Scott AM, Yeganeh S, Marks TJ, Ratner MA, Wasielewski MR. Ultrafast Intersystem Crossing and Spin Dynamics of Photoexcited Perylene-3,4:9,10-bis(dicarboximide) Covalently Linked to a Nitroxide Radical at Fixed Distances. J Am Chem Soc 2009; 131:3700-12. [DOI: 10.1021/ja808924f] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Emilie M. Giacobbe
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Qixi Mi
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael T. Colvin
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Boiko Cohen
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Charusheela Ramanan
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Amy M. Scott
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Sina Yeganeh
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Tobin J. Marks
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Mark A. Ratner
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael R. Wasielewski
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and International Institute for Nanotechnology, Northwestern University, Evanston, Illinois 60208-3113
| |
Collapse
|
25
|
Yeganeh S, Wasielewski MR, Ratner MA. Enhanced Intersystem Crossing in Three-Spin Systems: A Perturbation Theory Treatment. J Am Chem Soc 2009; 131:2268-73. [DOI: 10.1021/ja807590q] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Sina Yeganeh
- Department of Chemistry, Center for Nanofabrication and Molecular Self Assembly, Materials Research Science and Engineering Center, and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Michael R. Wasielewski
- Department of Chemistry, Center for Nanofabrication and Molecular Self Assembly, Materials Research Science and Engineering Center, and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| | - Mark A. Ratner
- Department of Chemistry, Center for Nanofabrication and Molecular Self Assembly, Materials Research Science and Engineering Center, and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113
| |
Collapse
|
26
|
Ciofini I, Adamo C, Teki Y, Tuyèras F, Lainé P. Reaching Optimal Light-Induced Intramolecular Spin Alignment within Photomagnetic Molecular Device Prototypes. Chemistry 2008; 14:11385-405. [DOI: 10.1002/chem.200801405] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
27
|
Teki Y, Tamekuni H, Haruta K, Takeuchi J, Miura Y. Design, synthesis, and uniquely electron-spin-polarized quartet photo-excited state of a π-conjugated spin system generated via the ion-pair state. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b714868b] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
28
|
Factors affecting light energy conversion in dual fluorophore-nitroxide molecules in solution and a protein. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880102125] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Donor-acceptor structures capable of retaining the charge-photoseparated state during the time long enough for secondary chemical reactions of these charges to occur attract special interest from the viewpoint of the problem of light energy utilization. We proposed dual fluorophore-nitroxide compounds (FNO•) as systems for the conversion of light energy to chemical energy. In these systems, the fluorophore segment in the excited singlet state serves as an electron donor, and the nitroxide segment is an electron acceptor. In FNO•, the photo- and chemical reduction of nitroxide results in the drastic decay of the electron spin resonance (ESR) signal from the nitroxide and the parallel enhancement of fluorescence. The same groups allow one to measure the factors affecting the electron transfer, namely, molecular dynamics and micropolarity of the medium in the vicinity of the donor (by fluorescence technique) and acceptor (by ESR) moieties. We demonstrate that in the dual probes the nitroxide segment is photoreduced to hydroxylamine in solution and in such nanoscale structures as serum albumins. The photoreduction occurs by very weak reducing agents (glycerol, ethanol, ethylene glycol, etc.) without a violation of the fluorophore structure. Therefore, photochemical reactions in the dual compounds with the formation of a reducing agent as hydroxyl amine can be considered as processes of light energy transfer. The nitroxide segment tethered to the donor-bridge-acceptor triad affects the photoseparated charge recombination via the mechanism of spin catalysis. Proficiency of the dual compounds for developing energy conversion systems can be extended by an optimal choice of the participants of the photochemical and -physical processes.
Collapse
|
29
|
Likhtenstein GI, Ishii K, Nakatsuji S. Dual chromophore-nitroxides: novel molecular probes, photochemical and photophysical models and magnetic materials. Photochem Photobiol 2007; 83:871-81. [PMID: 17645658 DOI: 10.1111/j.1751-1097.2007.00141.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Over the last decades scientists have faced growing requirements in novel methods of fast and sensitive analysis of antioxidant status of biological systems, spin redox probing and spin trapping, investigation of molecular dynamics, and of convenient models for studies of photophysical and photochemical processes. In approaching this problem, methods based upon the use of dual chromophore-nitroxide (CN) compounds have been suggested and developed. A CN consists of two molecular sub-functionality (a chromophore and a stable nitroxide radical) tethered together by spacers. In the dual compound the nitroxide is a strong intramolecular quencher of the fluorescence from the chromophore fragment. Reduction to hydroxylamine, oxidation of the nitroxide fragment or addition of an active radical yield the fluorescence increase and the parallel decay of the fragment electron spin resonance (ESR) signal. At certain conditions the dual molecules undergo photomagnetic switching and form excited state multi-spin systems. These unique properties of CN were intensively exploited as the basis for several methodologies, which include molecular probing, modeling intramolecular photochemical and photophysical processes, and construction of new magnetic materials.
Collapse
|
30
|
Kawai A, Shibuya K. Charge-Transfer Controlled Exchange Interaction in Radical-Triplet Encounter Pairs as Studied by FT-EPR Spectroscopy. J Phys Chem A 2007; 111:4890-901. [PMID: 17518447 DOI: 10.1021/jp067753d] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The exchange interaction, J, producing quartet and doublet energy separation in radical-triplet excited molecule encounter pairs, was investigated in solution by measuring chemically induced dynamic electron polarization (CIDEP) created through the radical-triplet pair mechanism. A time-resolved FT-EPR method was utilized to measure CIDEP of galvinoxyl radical by recording FID signals and an absolute magnitude of CIDEP, P(n), was determined for each radical-triplet system by detailed analysis of the time evolution curves of CIDEP. A transient FT-EPR signal phase remarkably depends on the triplet molecule. The signal phase is related to the sign of J value, which is responsible for the radical-triplet pair interaction. Most of galvinoxyl-triplet systems showed normal negative sign. An unusual positive sign was found in some systems characterized by a small energy gap, DeltaG, between the radical-triplet pair and intermolecular charge transfer (CT) states. A theoretical calculation of J value for radical-triplet encounter pairs was carried out by considering exchange integral and intermolecular CT interaction. According to the calculated J value and the diffusion theory for CIDEP magnitude, experimental Pn values were theoretically reproduced as a function of DeltaG. The present results confirm our previously reported CT model explaining the complicated nature of the sign of J value in the galvinoxyl-triplet encounter pairs. According to the proposed model for CT effect on J value and CIDEP results, nature of J value in radical-triplet pairs is discussed.
Collapse
Affiliation(s)
- Akio Kawai
- Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology, 2-12-1 Ohokayama, Tokyo 152-8551, Japan.
| | | |
Collapse
|