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Franz M, Neese F, Richert S. Elucidation of the exchange interaction in photoexcited three-spin systems - a second-order perturbational approach. Phys Chem Chem Phys 2024. [PMID: 39301612 DOI: 10.1039/d4cp03402c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024]
Abstract
Photogenerated three-spin systems show great potential for applications in the field of molecular spintronics. In these systems, the exchange interaction in the electronically excited state dictates their magnetic properties. To design such molecules for specific applications, it is thus important to understand how the sign and magnitude of the exchange interaction can be controlled. For this purpose, we developed a perturbational approach, based on previous work by the groups of de Loth and Malrieu, that allows for the direct calculation of the exchange interaction and its individual contributions up to the second order and implemented it within the ORCA program package. Within this manuscript, we present the derivation of the individual second-order contributions, provide an overview of the implementation of the code and illustrate its performance. We show that, using this perturbational approach in combination with state-averaged orbitals from minimal active space calculations, accurate values for the exchange interaction can be computed for organic nitroxides. Further, we demonstrate that the weight of the ionic determinants in the orbital optimisation of the CASSCF procedure is crucial for the computation of accurate exchange couplings. In the case of photoexcited chromophore-radical systems, we find that the dynamic spin polarisation effect constitutes the most important contribution to the exchange interaction, whereby the sign of this contribution determines the sign of the exchange interaction.
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Affiliation(s)
- Michael Franz
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany.
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2
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Zhang X, Chen X, Sun Y, Zhao J. Radical enhanced intersystem crossing mechanism, electron spin dynamics of high spin states and their applications in the design of heavy atom-free triplet photosensitizers. Org Biomol Chem 2024; 22:5257-5283. [PMID: 38884590 DOI: 10.1039/d4ob00520a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Heavy atom-free triplet photosensitizers (PSs) can overcome the high cost and biological toxicity of traditional molecular systems containing heavy atoms (such as Pt(II), Ir(III), Ru(II), Pd(II), Lu(III), I, or Br atoms) and, therefore, are developing rapidly. Connecting a stable free radical to the chromophore can promote the intersystem crossing (ISC) process through electron spin exchange interaction to produce the triplet state of the chromophore or the doublet (D) and quartet (Q) states when taking the whole spin system into account. These molecular systems based on the radical enhanced ISC (REISC) mechanism are important in the field of heavy atom-free triplet PSs. The REISC system has a simple molecular structure and good biocompatibility, and it is especially helpful for building high-spin quantum states (D and Q states) that have the potential to be developed as qubits in quantum information science. This review introduces the molecular structure design for the purpose of high-spin states. Time-resolved electron paramagnetic resonance (TREPR) is the most important characterization method to reveal the properties of these molecular systems, generation mechanism and electron spin polarization (ESP) of the high spin states. The spin polarization manipulation of high spin states and potential application in the field of quantum information engineering are also summarized. Moreover, molecular design principles of the REISC system to obtain long absorption wavelength, high triplet state quantum yield and long triplet state lifetime are introduced, as well as applications of the compounds in triplet-triplet annihilation upconversion, photodynamic therapy and bioimaging. This review is useful for the design of heavy atom-free triplet PSs based on the radical-chromophore molecular structure motif and the study of the photophysics of the compounds, as well as the electron spin dynamics of the multi electron system upon photoexcitation.
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Affiliation(s)
- Xue Zhang
- State Key Laboratory of Fine Chemicals, Frontiers Science Centre for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
| | - Xi Chen
- State Key Laboratory of Fine Chemicals, Frontiers Science Centre for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
| | - Yue Sun
- State Key Laboratory of Fine Chemicals, Frontiers Science Centre 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 Centre for Smart Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
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3
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Dhami S, Khatun MN, Sengupta C, Iyer PK, Pandey R. Substitution effects on the photoinduced excited state dynamics of perylenemonoimides in solution and thin films. Phys Chem Chem Phys 2024; 26:15600-15610. [PMID: 38757930 DOI: 10.1039/d4cp00993b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
Perylene monoimide (PMI) derivatives are attracting significant attention due to their strong absorption in the visible range, thermal stability, and synthetic accessibility. These properties make them promising for application in various areas such as optoelectronic devices, photosensitizers, etc. In this work, the photophysical properties and excited state dynamics of four different PMI derivatives (PMIB, BrPMITB, PMITB, and APITB) were studied in solution and thin films utilizing steady-state and time-resolved spectroscopic techniques. Among the four PMI derivatives, APITB is designed as a donor-acceptor dyad, with thianthrene as a donor and PMI as an acceptor. The activation of the triplet state through the spin-orbit charge transfer intersystem crossing (SOCT-ISC) process in THF was observed upon substitution with the thianthrene group at the peri position of the PMI moiety. The SOCT-ISC process facilitates triplet formation in the APITB dyad within 423 ps. Meanwhile, other PMI derivatives showed fluorescence within the femtosecond timescale in THF. The PMI derivatives in thin films displayed different photo physical properties to those in THF. This discrepancy arises due to the effective intermolecular coupling between the PMI derivatives in thin films.
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Affiliation(s)
- Suman Dhami
- Department of Chemistry, Indian Institute of Technology Roorkee, 247667 Haridwar, Uttarakhand, India.
| | - Mst Nasima Khatun
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
| | - Chaitrali Sengupta
- Department of Chemistry, Indian Institute of Technology Roorkee, 247667 Haridwar, Uttarakhand, India.
| | - Parameswar Krishnan Iyer
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
- Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Ravindra Pandey
- Department of Chemistry, Indian Institute of Technology Roorkee, 247667 Haridwar, Uttarakhand, India.
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4
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Thielert P, El Bitar Nehme M, Mayländer M, Franz M, Zimmermann SL, Fisch F, Gilch P, Vargas Jentzsch A, Rickhaus M, Richert S. Influence of the substitution position on spin communication in photoexcited perylene-nitroxide dyads. Chem Sci 2024; 15:7515-7523. [PMID: 38784753 PMCID: PMC11110163 DOI: 10.1039/d4sc00328d] [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: 01/15/2024] [Accepted: 03/25/2024] [Indexed: 05/25/2024] Open
Abstract
By virtue of the modularity of their structures, their tunable optical and magnetic properties, and versatile applications, photogenerated triplet-radical systems provide an ideal platform for the study of the factors controlling spin communication in molecular frameworks. Typically, these compounds consist of an organic chromophore covalently attached to a stable radical. After formation of the chromophore triplet state by photoexcitation, two spin centres are present in the molecule that will interact. The nature of their interaction is governed by the magnitude of the exchange interaction between them and can be studied by making use of transient electron paramagnetic resonance (EPR) techniques. Here, we investigate three perylene-nitroxide dyads that only differ with respect to the position where the nitroxide radical is attached to the perylene core. The comparison of the results from transient UV-vis and EPR experiments reveals major differences in the excited state properties of the three dyads, notably their triplet state formation yield, excited state deactivation kinetics, and spin coherence times. Spectral simulations and quantum chemical calculations are used to rationalise these findings and demonstrate the importance of considering the structural flexibility and the contribution of rotational conformers for an accurate interpretation of the data.
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Affiliation(s)
- Philipp Thielert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Mélissa El Bitar Nehme
- Department of Chemistry, University of Zurich Winterthurerstrasse 190 8057 Zurich Switzerland
| | - Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Michael Franz
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Simon L Zimmermann
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Fabienne Fisch
- Department of Chemistry, University of Zurich Winterthurerstrasse 190 8057 Zurich Switzerland
| | - Peter Gilch
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Andreas Vargas Jentzsch
- SAMS Research Group, Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22 67000 Strasbourg France
| | - Michel Rickhaus
- Department of Chemistry, University of Zurich Winterthurerstrasse 190 8057 Zurich Switzerland
- Department of Organic Chemistry, University of Geneva 30 Quai Ernest-Ansermet 1211 Geneva 4 Switzerland
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
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5
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Hudson JM, Evans EW. Radical Spin Polarization and Magnetosensitivity from Reversible Energy Transfer. J Phys Chem Lett 2024; 15:4130-4135. [PMID: 38593182 PMCID: PMC11033935 DOI: 10.1021/acs.jpclett.4c00656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 03/27/2024] [Accepted: 03/29/2024] [Indexed: 04/11/2024]
Abstract
Molecular spins provide potential building units for future quantum information science and spintronic technologies. In particular, doublet (S = 1/2) and triplet (S = 1) molecular spin states have the potential for excellent optical and spin properties for these applications if useful photon-spin mechanisms at room temperature can be devised. Here we explore the potential of exploiting reversible energy transfer between triplet and doublet states to establish magnetosensitive luminescence and spin polarization. We investigate the dependence of the photon-spin mechanism on the magnitude and sign of the exchange interaction between the doublet and triplet spin components in amorphous and crystalline model systems. The design of a magnetic field inclination sensor is proposed from understanding the required "structure" (spin interactions) to "function" (magnetosensitivity).
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Affiliation(s)
- John M. Hudson
- Department
of Chemistry, Swansea University, Swansea SA2 8PP, United Kingdom
- Centre
for Integrative Semiconductor Materials, Swansea SA1 8EN, United Kingdom
| | - Emrys W. Evans
- Department
of Chemistry, Swansea University, Swansea SA2 8PP, United Kingdom
- Centre
for Integrative Semiconductor Materials, Swansea SA1 8EN, United Kingdom
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6
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Kirk ML, Shultz DA, Marri AR, van der Est A. Photoinduced Magnetic Exchange-Jump Promotes Ground State Biradical Electron Spin Polarization. J Am Chem Soc 2024; 146:9285-9292. [PMID: 38518125 DOI: 10.1021/jacs.4c00930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024]
Abstract
Photoinduced electron spin polarization (ESP) is reported in the electronic ground states of three Pt(II) complexes comprised of two S = 1/2 nitronyl nitroxide (NN) radicals attached through different length para-phenylethynyl bridges to the 3,6 positions of a catecholate (CAT, donor) and 4,4'-di-tert-butyl-2,2'-bipyridine (bpy, acceptor). Complexes 1-3 have from 17 to 41 bonds separating NN radicals and display cw-EPR spectra consistent with |JNN-NN| ≫ |aN|, |JNN-NN| ≥ |aN|, and |JNN-NN| < |aN|, respectively, where JNN-NN is the magnetic exchange coupling between NN radicals in the electronic ground state, and aN is the isotropic 14N hyperfine coupling constant. Light-induced transient EPR spectra characterized as enhanced ground-state absorption were observed for all three complexes using 532 nm pulsed laser excitation into the ligand-to-ligand charge transfer (LL'CT) band of the (CAT)Pt(bpy) chromophore. The magnitude of the observed ESP increases in the order 1 < 2 < 3 and is inversely correlated with the magnitude of ground-state JNN-NN. In addition to the experimental observation of net absorptive polarization in 1-3, light excitation also produces multiplet polarization in 2. Since the weak dipolar coupling leads to a strong spectral overlap of the absorptive and emissive components, the multiplet polarization is not observed in 1 and 3 and is very weak in 2. The ability to spin-polarize multiple radical spins with a single photon is anticipated to advance new photoinduced multi qubit/qudit ESP protocols for quantum information science applications.
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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
- Center for Quantum Information and Control (CQuIC), The University of New Mexico, Albuquerque, New Mexico 87131-0001, United States
- Center for Computational Chemistry, The 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
| | - Anil Reddy Marri
- 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
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7
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Zhang H, Ren G, Hou W, Wang L, Sun Y, Liu J. A Silicon-Rhodamine-Based Heavy-Atom-Free Photosensitizer for Mitochondria-targeted Photodynamic Therapy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 308:123688. [PMID: 38042121 DOI: 10.1016/j.saa.2023.123688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/17/2023] [Accepted: 11/26/2023] [Indexed: 12/04/2023]
Abstract
Silicon-xanthene derivatives (SiXs) have gained popularity in the field of bioimaging due to their advantageous far-red to near-infrared (NIR) absorption and emission wavelengths, notable brightness (ε × Φ), inherent mitochondrial targeting properties and high photo-stability, making them an excellent candidate for photodynamic therapy (PDT). Nevertheless, the utilization of SiXs as photosensitizers (PSs) for PDT in cancer treatment remains largely unexplored, primarily due to their limited capacity to generate cytotoxic reactive oxygen species (ROS). However, the potential of SiXs in PDT warrants further investigation. In this study, utilizing the spin-orbit charge transfer-induced intersystem crossing (SOCT-ISC) mechanism, we reported one novel heavy-atom-free, mitochondria-targeted, silicon-rhodamine-based photosensitizer (SiR-PXZ), which demonstrated excellent biocompatibility, minimal dark toxicity, favorable water-solubility and stability, and considerable singlet oxygen quantum yield under 660 nm light irradiation (ΦΔ = 0.16 in air-saturated PBS). Moreover, SiR-PXZ could be rapidly taken up by the mitochondria and efficiently induced apoptosis of cancer cells with an IC50 value of 1.2 μM. The in vivo studies showed that SiR-PXZ exhibited excellent anti-tumor effects, making it potentially valuable for clinical application. This study offers a source of ideas for the construction of SiXs-based photosensitizers for photodynamic cancer treatment in the future.
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Affiliation(s)
- Hongxing Zhang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Guoxi Ren
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Wenhua Hou
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Lijuan Wang
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China
| | - Yuanqiang Sun
- College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
| | - Jing Liu
- School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, China.
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8
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Kopp K, Westhofen L, Hett T, Felix Schwering-Sohnrey M, Mayländer M, Richert S, Schiemann O. Synthesis and dark state EPR properties of PDI-trityl dyads and triads. Chemistry 2024; 30:e202303635. [PMID: 38055217 DOI: 10.1002/chem.202303635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/06/2023] [Accepted: 12/06/2023] [Indexed: 12/07/2023]
Abstract
Covalently-linked chromophore-radical systems with their unique optical and magnetic properties are useful for applications in, e. g., quantum information science. To expand the catalog of molecular systems, we synthesized and characterized six novel chromophore-radical and radical-chromophore-radical systems employing derivatives of perylene diimide (PDI) as the chromophore and trityl as the radical. The EPR properties of these compounds were evaluated in solution at cryogenic and room temperatures. In addition, the electron spin-spin coupling in the two bistrityl systems was investigated using DQC measurements. The presented results serve as a basis for further spectroscopic investigations under photoexcitation of the PDI core.
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Affiliation(s)
- Kevin Kopp
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Lars Westhofen
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Tobias Hett
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | | | - Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104, Freiburg, Germany
| | - Olav Schiemann
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
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9
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Mizuno A, Matsuoka R, Mibu T, Kusamoto T. Luminescent Radicals. Chem Rev 2024; 124:1034-1121. [PMID: 38230673 DOI: 10.1021/acs.chemrev.3c00613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Organic radicals are attracting increasing interest as a new class of molecular emitters. They demonstrate electronic excitation and relaxation dynamics based on their doublet or higher multiplet spin states, which are different from those based on singlet-triplet manifolds of conventional closed-shell molecules. Recent studies have disclosed luminescence properties and excited state dynamics unique to radicals, such as highly efficient electron-photon conversion in OLEDs, NIR emission, magnetoluminescence, an absence of heavy atom effect, and spin-dependent and spin-selective dynamics. These are difficult or sometimes impossible to achieve with closed-shell luminophores. This review focuses on luminescent organic radicals as an emerging photofunctional molecular system, and introduces the material developments, fundamental properties including luminescence, and photofunctions. Materials covered in this review range from monoradicals, radical oligomers, and radical polymers to metal complexes with radical ligands demonstrating radical-involved emission. In addition to stable radicals, transiently formed radicals generated in situ by external stimuli are introduced. This review shows that luminescent organic radicals have great potential to expand the chemical and spin spaces of luminescent molecular materials and thus broaden their applicability to photofunctional systems.
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Affiliation(s)
- Asato Mizuno
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Ryota Matsuoka
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, HayamaKanagawa 240-0193, Japan
| | - Takuto Mibu
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Tetsuro Kusamoto
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, HayamaKanagawa 240-0193, Japan
- JST-PRESTO, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
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10
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Kandrashkin YE. Estimation of Heisenberg exchange interaction in rigid photoexcited chromophore-radical compound by transient EPR. J Chem Phys 2024; 160:044306. [PMID: 38284654 DOI: 10.1063/5.0188404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 01/04/2024] [Indexed: 01/30/2024] Open
Abstract
The magnetic field dependence of the spin polarization in a photoexcited rigid chromophore-radical conjugate is theoretically investigated. The excitation of the chromophore-radical conjugate often populates the metastable doublet and quartet states formed by the interactions of the unpaired electrons of the triplet chromophore and the radical. The intensities of the +1/2 ↔ - 1/2 transitions of the doublet and quartet manifolds are sensitive to the ratio jω = 3J/ω0 between the triplet-doublet exchange interaction J and the Zeeman energy ω0. It is shown that the analytical expressions of these intensities previously found for the triplet mechanism of the initial spin polarization can be expanded and applied to a broader class of compounds that may have other intersystem crossing pathways of the depopulation of the excited singlet state of the chromophore. It is also shown that the exchange interaction can be evaluated not only by comparing the electron paramagnetic resonance spectra obtained in different microwave frequency bands but also by comparing the data obtained in the same microwave band but with a shift of the frequency of the resonator. The results obtained broaden the potential applications of the previously proposed approach for analyzing the correlation between the exchange coupling and the distance separating the radical and the chromophore spins, as well as the structure of the bridge connecting their fragments.
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Affiliation(s)
- Yuri E Kandrashkin
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract 10/7, Kazan 420029, Russia
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11
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Qiu Y, Eckvahl HJ, Equbal A, Krzyaniak MD, Wasielewski MR. Enhancing Coherence Times of Chromophore-Radical Molecular Qubits and Qudits by Rational Design. J Am Chem Soc 2023; 145:25903-25909. [PMID: 37963349 DOI: 10.1021/jacs.3c10772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2023]
Abstract
An important criterion for quantum operations is long qubit coherence times. To elucidate the influence of molecular structure on the coherence times of molecular spin qubits and qudits, a series of molecules featuring perylenediimide (PDI) chromophores covalently linked to stable nitroxide radicals were synthesized and investigated by pulse electron paramagnetic resonance spectroscopy. Photoexcitation of PDI in these systems creates an excited quartet state (Q) followed by a spin-polarized doublet ground state (D0), which hold promise as spin qudits and qubits, respectively. By tailoring the molecular structure of these spin qudit/qubit candidates by selective deuteration and eliminating intramolecular motion, coherence times of Tm = 9.1 ± 0.3 and 4.2 ± 0.3 μs at 85 K for D0 and Q, respectively, are achieved. These coherence times represent a nearly 3-fold enhancement compared to those of the initial molecular design. This approach offers a rational structural design protocol for effectively extending coherence times in molecular spin qudits/qubits.
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Affiliation(s)
- Yunfan Qiu
- Department of Chemistry, Center for Molecular Quantum Transduction, and Paula M. Trienens Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3313, United States
| | - Hannah J Eckvahl
- Department of Chemistry, Center for Molecular Quantum Transduction, and Paula M. Trienens Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3313, United States
| | - Asif Equbal
- Department of Chemistry, Center for Molecular Quantum Transduction, and Paula M. Trienens Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3313, United States
| | - Matthew D Krzyaniak
- Department of Chemistry, Center for Molecular Quantum Transduction, and Paula M. Trienens Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3313, United States
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, and Paula M. Trienens Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3313, United States
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12
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Mayländer M, Kopp K, Nolden O, Franz M, Thielert P, Vargas Jentzsch A, Gilch P, Schiemann O, Richert S. PDI-trityl dyads as photogenerated molecular spin qubit candidates. Chem Sci 2023; 14:10727-10735. [PMID: 37829028 PMCID: PMC10566479 DOI: 10.1039/d3sc04375d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
Owing to their potential applications in the field of quantum information science, photogenerated organic triplet-radical conjugates have attracted an increasing amount of attention recently. Typically, these compounds are composed of a chromophore appended to a stable radical. After initialisation of the system by photoexcitation, a highly spin-polarised quartet state may be generated, which serves as a molecular spin qubit candidate. Here, we investigate three perylene diimide (PDI)-based chromophore-radical systems with different phenylene linkers and radical counterparts by both optical spectroscopy and transient electron paramagnetic resonance (EPR) techniques. Femtosecond transient absorption measurements demonstrate chromophore triplet state formation on a picosecond time scale for PDI-trityl dyads, while excited state deactivation is found to be slowed down considerably in a PDI-nitroxide analogue. The subsequent investigation of the coherent spin properties by transient EPR confirms quartet state formation by triplet-doublet spin mixing for all investigated dyads and the suitability of the two studied PDI-trityl dyads as spin qubit candidates. In particular, we show that using tetrathiaryl trityl as the radical counterpart, an intense spin polarisation is observed even at room temperature and quartet state coherence times of 3.0 μs can be achieved at 80 K, which represents a considerable improvement compared to previously studied systems.
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Affiliation(s)
- Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Kevin Kopp
- Clausius Institute of Physical and Theoretical Chemistry, University of Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Oliver Nolden
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Michael Franz
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Philipp Thielert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Andreas Vargas Jentzsch
- SAMS Research Group, Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22 67000 Strasbourg France
| | - Peter Gilch
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Olav Schiemann
- Clausius Institute of Physical and Theoretical Chemistry, University of Bonn Wegelerstraße 12 53115 Bonn Germany
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
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13
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Kirk ML, Shultz DA, Hewitt P, Marri AR, van der Est A. Competitive reversed quartet mechanisms for photogenerated ground state electron spin polarization. Chem Sci 2023; 14:9689-9695. [PMID: 37736649 PMCID: PMC10510625 DOI: 10.1039/d3sc03049k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/06/2023] [Indexed: 09/23/2023] Open
Abstract
Photoinduced electron spin polarization (ESP) of a spin-½ organic radical (nitronyl nitroxide, NN) in a series of Pt(ii) complexes comprised of 4,4'-di-tert-butyl-2,2'-bipyridine (bpy) and 3-tert-butylcatecholate (CAT) ligands, where the CAT ligand is substituted with (CH3)n-meta-phenyl-NN (bridge-NN) groups, is presented and discussed. We show the importance of attenuating the energy gap between localized NN radical and chromophoric excited states to control both the magnitude and sign of the optically-generated ESP, and to provide deeper insight into the details of the ESP mechanism. Understanding electronic structure contributions to optically generated ESP will enhance our ability to control the nature of prepared states for a variety of quantum information science applications, where strong ESP facilitates enhanced sensitivity and readout capabilities at low applied magnetic fields and higher temperatures.
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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
- The Center for High Technology Materials, The University of New Mexico Albuquerque New Mexico 87106 USA
- Center for Quantum Information and Control (CQuIC), The University of New Mexico Albuquerque New Mexico 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
| | - Anil Reddy Marri
- Department of Chemistry, North Carolina State University Raleigh North Carolina 27695-8204 USA
| | - Art van der Est
- Department of Chemistry, Brock University St. Catharines Ontario Canada L2S 3A1
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14
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Gorgon S, Lv K, Grüne J, Drummond BH, Myers WK, Londi G, Ricci G, Valverde D, Tonnelé C, Murto P, Romanov AS, Casanova D, Dyakonov V, Sperlich A, Beljonne D, Olivier Y, Li F, Friend RH, Evans EW. Reversible spin-optical interface in luminescent organic radicals. Nature 2023; 620:538-544. [PMID: 37587296 PMCID: PMC10432275 DOI: 10.1038/s41586-023-06222-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 05/16/2023] [Indexed: 08/18/2023]
Abstract
Molecules present a versatile platform for quantum information science1,2 and are candidates for sensing and computation applications3,4. Robust spin-optical interfaces are key to harnessing the quantum resources of materials5. To date, carbon-based candidates have been non-luminescent6,7, which prevents optical readout via emission. Here we report organic molecules showing both efficient luminescence and near-unity generation yield of excited states with spin multiplicity S > 1. This was achieved by designing an energy resonance between emissive doublet and triplet levels, here on covalently coupled tris(2,4,6-trichlorophenyl) methyl-carbazole radicals and anthracene. We observed that the doublet photoexcitation delocalized onto the linked acene within a few picoseconds and subsequently evolved to a pure high-spin state (quartet for monoradical, quintet for biradical) of mixed radical-triplet character near 1.8 eV. These high-spin states are coherently addressable with microwaves even at 295 K, with optical readout enabled by reverse intersystem crossing to emissive states. Furthermore, for the biradical, on return to the ground state the previously uncorrelated radical spins either side of the anthracene shows strong spin correlation. Our approach simultaneously supports a high efficiency of initialization, spin manipulations and light-based readout at room temperature. The integration of luminescence and high-spin states creates an organic materials platform for emerging quantum technologies.
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Affiliation(s)
- Sebastian Gorgon
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
- Centre for Advanced Electron Spin Resonance, Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, UK.
| | - Kuo Lv
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
| | - Jeannine Grüne
- Experimental Physics VI, Faculty of Physics and Astronomy, University of Würzburg, Würzburg, Germany
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | | | - William K Myers
- Centre for Advanced Electron Spin Resonance, Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, UK
| | - Giacomo Londi
- Laboratory for Computational Modelling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Namur, Belgium
| | - Gaetano Ricci
- Laboratory for Computational Modelling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Namur, Belgium
| | - Danillo Valverde
- Laboratory for Computational Modelling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Namur, Belgium
| | | | - Petri Murto
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | | | | | - Vladimir Dyakonov
- Experimental Physics VI, Faculty of Physics and Astronomy, University of Würzburg, Würzburg, Germany
| | - Andreas Sperlich
- Experimental Physics VI, Faculty of Physics and Astronomy, University of Würzburg, Würzburg, Germany
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons, Belgium
| | - Yoann Olivier
- Laboratory for Computational Modelling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Namur, Belgium
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
| | | | - Emrys W Evans
- Department of Chemistry, Swansea University, Swansea, UK.
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15
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Zhu W, Wu Y, Zhang Y, Sukhanov AA, Chu Y, Zhang X, Zhao J, Voronkova VK. Preparation of Xanthene-TEMPO Dyads: Synthesis and Study of the Radical Enhanced Intersystem Crossing. Int J Mol Sci 2023; 24:11220. [PMID: 37446398 DOI: 10.3390/ijms241311220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/03/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
We prepared a rhodamine-TEMPO chromophore-radical dyad (RB-TEMPO) to study the radical enhanced intersystem crossing (REISC). The visible light-harvesting chromophore rhodamine is connected with the TEMPO (a nitroxide radical) via a C-N bond. The UV-vis absorption spectrum indicates negligible electron interaction between the two units at the ground state. Interestingly, the fluorescence of the rhodamine moiety is strongly quenched in RB-TEMPO, and the fluorescence lifetime of the rhodamine moiety is shortened to 0.29 ns, from the lifetime of 3.17 ns. We attribute this quenching effect to the intramolecular electron spin-spin interaction between the nitroxide radical and the photoexcited rhodamine chromophore. Nanosecond transient absorption spectra confirm the REISC in RB-TEMPO, indicated by the detection of the rhodamine chromophore triplet excited state; the lifetime was determined as 128 ns, which is shorter than the native rhodamine triplet state lifetime (0.58 μs). The zero-field splitting (ZFS) parameters of the triplet state of the chromophore were determined with the pulsed laser excited time-resolved electron paramagnetic resonance (TREPR) spectra. RB-TEMPO was used as a photoinitiator for the photopolymerization of pentaerythritol triacrylate (PETA). These studies are useful for the design of heavy atom-free triplet photosensitizers, the study of the ISC, and the electron spin dynamics of the radical-chromophore systems upon photoexcitation.
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Affiliation(s)
- Wenhui Zhu
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Yanran Wu
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Yiyan Zhang
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Andrey A Sukhanov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of Russian Academy of Sciences, Kazan 420029, Russia
| | - Yuqi Chu
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Xue Zhang
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology, 2 Ling Gong Road, Dalian 116024, China
| | - Violeta K Voronkova
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of Russian Academy of Sciences, Kazan 420029, Russia
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16
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Mayländer M, Thielert P, Quintes T, Vargas Jentzsch A, Richert S. Room Temperature Electron Spin Coherence in Photogenerated Molecular Spin Qubit Candidates. J Am Chem Soc 2023. [PMID: 37337625 DOI: 10.1021/jacs.3c04021] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
One of the main challenges in the emerging field of molecular spintronics is the identification of new spin qubit materials for quantum information applications. In this regard, recent work has shown that photoexcited chromophore-radical systems are promising candidates to expand our repertoire of suitable candidate molecules. Here, we investigate a series of three chromophore-radical compounds composed of a perylene diimide (PDI) chromophore and a stable 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) radical by transient electron paramagnetic resonance (EPR) techniques. We explore the influence of isotope labeling of the TEMPO moiety on the EPR spectra and electron spin coherence times of the molecular quartet states generated upon photoexcitation and illustrate that (i) a coherent manipulation of the spin state is possible in these systems even at room temperature and that (ii) a spin coherence time of 0.7 μs can be achieved under these conditions. This demonstration of electron spin coherence at ambient temperatures paves the way for practical applications of such systems in functional molecular devices.
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Affiliation(s)
- Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - Philipp Thielert
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - Theresia Quintes
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - Andreas Vargas Jentzsch
- SAMS Research Group, Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22, 67000 Strasbourg, France
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
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17
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Mayländer M, Quintes T, Franz M, Allonas X, Vargas Jentzsch A, Richert S. Distance dependence of enhanced intersystem crossing in BODIPY-nitroxide dyads. Chem Sci 2023; 14:5361-5368. [PMID: 37234885 PMCID: PMC10207891 DOI: 10.1039/d3sc00589e] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
Photogenerated organic triplet-doublet systems have attracted an increasing amount of attention in recent years due to their versatility and suitability for a range of technological applications in the emerging field of molecular spintronics. Such systems are typically generated by enhanced intersystem crossing (EISC) preceded by photoexcitation of an organic chromophore covalently linked to a stable radical. After formation of the chromophore triplet state by EISC, triplet state and stable radical may interact, whereby the nature of the interaction depends on the exchange interaction JTR between them. If JTR surpasses all other magnetic interactions in the system, molecular quartet states may be formed by spin mixing. For the design of new spintronic materials based on photogenerated triplet-doublet systems, it is crucial to gain further knowledge about the factors influencing the EISC process and the yield of the subsequent quartet state formation. Here we investigate a series of three BODIPY-nitroxide dyads characterised by different separation distances and different relative orientations of the two spin centres. Our combined results from optical spectroscopy, transient electron paramagnetic resonance, and quantum chemical calculations suggest that the chromophore triplet formation by EISC is mediated by dipolar interactions and depends primarily on the distance between the chromophore and radical electrons, while the yield of the subsequent quartet state formation by triplet-doublet spin mixing is influenced by the absolute magnitude of JTR.
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Affiliation(s)
- Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Theresia Quintes
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Michael Franz
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Xavier Allonas
- Laboratoire de Photochimie et d'Ingénierie Macromoléculaires, Institut Jean Baptiste Donnet 3b rue Alfred Werner 68093 Mulhouse Cedex France
| | - Andreas Vargas Jentzsch
- SAMS Research Group, Université de Strasbourg, CNRS, Institut Charles Sadron UPR 22 67000 Strasbourg France
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
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18
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Tait CE, Krzyaniak MD, Stoll S. Computational tools for the simulation and analysis of spin-polarized EPR spectra. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 349:107410. [PMID: 36870248 DOI: 10.1016/j.jmr.2023.107410] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/10/2023] [Accepted: 02/18/2023] [Indexed: 06/18/2023]
Abstract
The EPR spectra of paramagnetic species induced by photoexcitation typically exhibit enhanced absorptive and emissive features resulting from sublevel populations that differ from thermal equilibrium. The populations and the resulting spin polarization of the spectra are dictated by the selectivity of the photophysical process generating the observed state. Simulation of the spin-polarized EPR spectra is crucial in the characterization of both the dynamics of formation of the photoexcited state as well as its electronic and structural properties. EasySpin, the simulation toolbox for EPR spectroscopy, now includes extended support for the simulation of the EPR spectra of spin-polarized states of arbitrary spin multiplicity and formed by a variety of different mechanisms, including photoexcited triplet states populated by intersystem crossing, charge recombination or spin polarization transfer, spin-correlated radical pairs created by photoinduced electron transfer, triplet pairs formed by singlet fission and multiplet states arising from photoexcitation in systems containing chromophores and stable radicals. In this paper, we highlight EasySpin's capabilities for the simulation of spin-polarized EPR spectra on the basis of illustrative examples from the literature in a variety of fields ranging across chemistry, biology, material science and quantum information science.
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Affiliation(s)
- Claudia E Tait
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, United Kingdom.
| | - Matthew D Krzyaniak
- Department of Chemistry, Center for Molecular Quantum Transduction and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston 60208, IL, United States
| | - Stefan Stoll
- Department of Chemistry, University of Washington, Seattle, 98195, WA, United States
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19
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Heavy Atom-Free Triplet Photosensitizers: Molecular Structure Design, Photophysical Properties and Application in Photodynamic Therapy. Molecules 2023; 28:molecules28052170. [PMID: 36903415 PMCID: PMC10004235 DOI: 10.3390/molecules28052170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/08/2023] [Accepted: 02/22/2023] [Indexed: 03/03/2023] Open
Abstract
Photodynamic therapy (PDT) is a promising method for the treatment of cancer, because of its advantages including a low toxicity, non-drug-resistant character, and targeting capability. From a photochemical aspect, a critical property of triplet photosensitizers (PSs) used for PDT reagents is the intersystem crossing (ISC) efficiency. Conventional PDT reagents are limited to porphyrin compounds. However, these compounds are difficult to prepare, purify, and derivatize. Thus, new molecular structure paradigms are desired to develop novel, efficient, and versatile PDT reagents, especially those contain no heavy atoms, such as Pt or I, etc. Unfortunately, the ISC ability of heavy atom-free organic compounds is usually elusive, and it is difficult to predict the ISC capability of these compounds and design novel heavy atom-free PDT reagents. Herein, from a photophysical perspective, we summarize the recent developments of heavy atom-free triplet PSs, including methods based on radical-enhanced ISC (REISC, facilitated by electron spin-spin interaction), twisted π-conjugation system-induced ISC, the use of fullerene C60 as an electron spin converter in antenna-C60 dyads, energetically matched S1/Tn states-enhanced ISC, etc. The application of these compounds in PDT is also briefly introduced. Most of the presented examples are the works of our research group.
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20
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Qiu Y, Equbal A, Lin C, Huang Y, Brown PJ, Young RM, Krzyaniak MD, Wasielewski MR. Optical Spin Polarization of a Narrow-Linewidth Electron-Spin Qubit in a Chromophore/Stable-Radical System. Angew Chem Int Ed Engl 2023; 62:e202214668. [PMID: 36469535 PMCID: PMC10107609 DOI: 10.1002/anie.202214668] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/29/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Photoexcited organic chromophores appended to stable radicals can serve as qubit and/or qudit candidates for quantum information applications. 1,6,7,12-Tetra-(4-tert-butylphenoxy)-perylene-3,4 : 9,10-bis(dicarboximide) (tpPDI) linked to a partially deuterated α,γ-bisdiphenylene-β-phenylallyl radical (BDPA-d16 ) was synthesized and characterized by time-resolved optical and electron paramagnetic resonance (EPR) spectroscopies. Photoexcitation of tpPDI-BDPA-d16 results in ultrafast radical-enhanced intersystem crossing to produce a quartet state (Q) followed by formation of a spin-polarized doublet ground state (D0 ). Pulse-EPR experiments confirmed the spin multiplicity of Q and yielded coherence times of Tm =2.1±0.1 μs and 2.8±0.2 μs for Q and D0 , respectively. BDPA-d16 eliminates the dominant 1 H hyperfine couplings, resulting in a single narrow line for both the Q and D0 states, which enhances the spectral resolution needed for good qubit addressability.
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Affiliation(s)
- Yunfan Qiu
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Asif Equbal
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Chenjian Lin
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Yuheng Huang
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Paige J Brown
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Ryan M Young
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Matthew D Krzyaniak
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL 60208-3113, USA
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21
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Lu C, Cho E, Cui Z, Gao Y, Cao W, Brédas JL, Coropceanu V, Li F. Towards Efficient and Stable Donor-Acceptor Luminescent Radicals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208190. [PMID: 36417767 DOI: 10.1002/adma.202208190] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/01/2022] [Indexed: 06/16/2023]
Abstract
In contrast to closed-shell luminescent molecules, the electronic ground state and lowest excited state in organic luminescent radicals are both spin doublet, which results in spin-allowed radiative transitions. Most reported luminescent radicals with high photoluminescent quantum efficiency (PLQE) have a donor-acceptor (D-A•) chemical structure where an electron-donating group is covalently attached to an electron-withdrawing radical core (A•). Understanding the main factors that define the efficiency and stability of D-A• type luminescent radicals remains challenging. Here, we designed and synthesized a series of tri(2,4,6-trichlorophenyl)methyl (TTM) radical derivatives with donor substituents varying by their extent of conjugation and their number of imine-type nitrogen atoms. The experimental results suggest that the luminescence efficiency and stability of the radicals are proportional to the degree of conjugation but inversely proportional to the number of imine nitrogen atoms in the substituents. These experimental trends are very well reproduced by density functional theory calculations. The theoretical results indicate that both the luminescence efficiency and radical stability are related to the energy difference between the charge transfer (CT) and local-excitation (LE) states, which decreases as either the number of imine nitrogen atoms in the substituent increases or its conjugation length decreases.
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Affiliation(s)
- Chen Lu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Eunkyung Cho
- Department of Chemistry and Biochemistry, University of Arizona College of Science, Tucson, AZ, 85721-0088, USA
| | - Zhiyuan Cui
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yuhang Gao
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Wenjuan Cao
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Jean-Luc Brédas
- Department of Chemistry and Biochemistry, University of Arizona College of Science, Tucson, AZ, 85721-0088, USA
| | - Veaceslav Coropceanu
- Department of Chemistry and Biochemistry, University of Arizona College of Science, Tucson, AZ, 85721-0088, USA
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
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22
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Manian A, Hudson RJ, Ramkissoon P, Smith TA, Russo SP. Interexcited State Photophysics I: Benchmarking Density Functionals for Computing Nonadiabatic Couplings and Internal Conversion Rate Constants. J Chem Theory Comput 2023; 19:271-292. [PMID: 36490305 DOI: 10.1021/acs.jctc.2c00888] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We present the first benchmarking study of nonadiabatic matrix coupling elements (NACMEs) calculated using different density functionals. Using the S1 → S0 transition in perylene solvated in toluene as a case study, we calculate the photophysical properties and corresponding rate constants for a variety of density functionals from each rung of Jacob's ladder. The singlet photoluminescence quantum yield (sPLQY) is taken as a measure of accuracy, measured experimentally here as 0.955. Important quantum chemical parameters such as geometries, absorption, emission, and adiabatic energies, NACMEs, Hessians, and transition dipole moments were calculated for each density functional basis set combination (data set) using density functional theory based multireference configuration interaction (DFT/MRCI) and compared to experiment where possible. We were able to derive simple relations between the TDDFT and DFT/MRCI photophysical properties; with semiempirical damping factors of ∼0.843 ± 0.017 and ∼0.954 ± 0.064 for TDDFT transition dipole moments and energies to DFT/MRCI level approximations, respectively. NACMEs were dominated by out-of-plane derivative components belonging to the center-most ring atoms with weaker contributions from perturbations along the transverse and longitudinal axes. Calculated theoretical spectra compared well to both experiment and literature, with fluorescence lifetimes between 7.1 and 12.5 ns, agreeing within a factor of 2 with experiment. Internal conversion (IC) rates were then calculated and were found to vary wildly between 106-1016 s-1 compared with an experimental rate of the order 107 s-1. Following further testing by mixing data sets, we found a strong dependence on the method used to obtain the Hessian. The 5 characterized data sets ranked in order of most promising are PBE0/def2-TZVP, ωB97XD/def2-TZVP, HCTH407/TZVP, PBE/TZVP, and PBE/def2-TZVP.
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Affiliation(s)
- Anjay Manian
- ARC Centre of Excellence in Exciton Science, School of Science, RMIT University, Melbourne3000, Australia
| | - Rohan J Hudson
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville3010, Australia
| | - Pria Ramkissoon
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville3010, Australia
| | - Trevor A Smith
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Melbourne, Parkville3010, Australia
| | - Salvy P Russo
- ARC Centre of Excellence in Exciton Science, School of Science, RMIT University, Melbourne3000, Australia
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23
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Properties and applications of photoexcited chromophore–radical systems. Nat Rev Chem 2023; 7:75-90. [PMID: 37117913 DOI: 10.1038/s41570-022-00453-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2022] [Indexed: 02/11/2023]
Abstract
Photoexcited organic chromophore-radical systems hold great promise for a range of technological applications in molecular spintronics, including quantum information technology and artificial photosynthesis. However, further development of such systems will depend on the ability to control the magnetic properties of these materials, which requires a profound understanding of the underlying excited-state dynamics. In this Review, we discuss photogenerated triplet-doublet systems and their potential to be used for applications in molecular spintronics. We outline the theoretical description of the spin system in the different coupling regimes and the invoked excited-state mechanisms governing the generation and transfer of spin polarization. The main characterization techniques used to evaluate the optical and magnetic properties of chromophore-radical systems are discussed. We conclude by giving an overview of previously investigated covalently linked triplet-radical systems, and highlight the need for further systematic investigations to improve our understanding of the magnetic interactions in such systems.
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24
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Mao H, Young RM, Krzyaniak MD, Wasielewski MR. Optical Initialization of Molecular Qubit Spin States Using Weak Exchange Coupling to Photogenerated Fullerene Triplet States. J Phys Chem B 2022; 126:10519-10527. [DOI: 10.1021/acs.jpcb.2c07096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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
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25
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Franz M, Neese F, Richert S. Calculation of exchange couplings in the electronically excited state of molecular three-spin systems. Chem Sci 2022; 13:12358-12366. [PMID: 36382276 PMCID: PMC9629084 DOI: 10.1039/d2sc04701b] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 09/17/2022] [Indexed: 09/19/2023] Open
Abstract
Photogenerated molecular three-spin systems, composed of a chromophore and a covalently bound stable radical, are promising candidates for applications in the field of molecular spintronics. Through excitation with light, an excited doublet state and a quartet state are generated, whereby their energy difference depends on the exchange interaction J TR between the chromophore triplet state (T) and the stable radical (R). In order to establish design rules for new materials to be used in molecular spintronics devices, it is of great importance to gain knowledge on the magnitude of J TR as well as the factors influencing J TR on a molecular level. Here, we present a robust and reliable computational method to determine excited state exchange couplings in three-electron-three-centre systems based on a CASSCF/QD-NEVPT2 approach. The methodology is benchmarked and then applied to a series of molecules composed of a perylene chromophore covalently linked to various stable radicals. We calculate the phenomenological exchange interaction J TR between chromophore and radical, which can be compared directly to the experiment, but also illustrate how the individual exchange interactions J ij can be extracted using an effective Hamiltonian that corresponds to the Heisenberg-Dirac-Van-Vleck Hamiltonian. The latter procedure enables a more detailed analysis of the contributions to the exchange interaction J TR and yields additional insight that will be invaluable for future design optimisation.
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Affiliation(s)
- Michael Franz
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Germany
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
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26
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Fedyushin PA, Akyeva AY, Syroeshkin MA, Rybalova TV, Stass DV, Korolev VA, Tretyakov EV, Egorov MP. Synthesis, structure, and properties of tert-butyl perfluorobiphenyl nitroxide. Russ Chem Bull 2022. [DOI: 10.1007/s11172-022-3553-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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27
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Mayländer M, Nolden O, Franz M, Chen S, Bancroft L, Qiu Y, Wasielewski MR, Gilch P, Richert S. Accessing the triplet state of perylenediimide by radical-enhanced intersystem crossing. Chem Sci 2022; 13:6732-6743. [PMID: 35756510 PMCID: PMC9172295 DOI: 10.1039/d2sc01899c] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/10/2022] [Indexed: 12/27/2022] Open
Abstract
Owing to their exceptional photophysical properties and high photostability, perylene diimide (PDI) chromophores have found various applications as building blocks of materials for organic electronics. In many light-induced processes in PDI derivatives, chromophore excited states with high spin multiplicities, such as triplet or quintet states, have been revealed as key intermediates. The exploration of their properties and formation conditions is thus expected to provide invaluable insight into their underlying photophysics and promises to reveal strategies for increasing the performance of optoelectronic devices. However, accessing these high-multiplicity excited states of PDI to increase our mechanistic understanding remains a difficult task, due to the fact that the lowest excited singlet state of PDI decays with near-unity quantum yield to its ground state. Here we make use of radical-enhanced intersystem crossing (EISC) to generate the PDI triplet state in high yield. One or two 2,2,6,6-tetramethylpiperidinyloxyl (TEMPO) stable radicals were covalently attached to the imide position of PDI chromophores with and without p-tert-butylphenoxy core substituents. By combining femtosecond UV-vis transient absorption and transient electron paramagnetic resonance spectroscopies, we demonstrate strong magnetic exchange coupling between the PDI triplet state and TEMPO, resulting in the formation of excited quartet or quintet states. Important differences in the S1 state deactivation rate constants and triplet yields are observed for compounds bearing PDI moieties with different core substitution patterns. We show that these differences can be rationalized by considering the varying importance of competitive excited state decay processes, such as electron and excitation energy transfer. The comparison of the results obtained for different PDI–TEMPO derivatives leads us to propose design guidelines for optimizing the efficiency of triplet sensitization in molecular assemblies by EISC. The triplet state of PDI can be sensitized efficiently by radical-enhanced intersystem crossing. A detailed study of several related structures allows us to propose new strategies to optimize triplet formation in materials for optoelectronic devices.![]()
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Affiliation(s)
- Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Oliver Nolden
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1 40225 Düsseldorf Germany
| | - Michael Franz
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
| | - Su Chen
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University 2145 Sheridan Road Evanston IL 60208-3113 USA
| | - Laura Bancroft
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University 2145 Sheridan Road Evanston IL 60208-3113 USA
| | - Yunfan Qiu
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University 2145 Sheridan Road Evanston IL 60208-3113 USA
| | - Michael R Wasielewski
- Department of Chemistry, Center for Molecular Quantum Transduction, Institute for Sustainability and Energy at Northwestern, Northwestern University 2145 Sheridan Road Evanston IL 60208-3113 USA
| | - Peter Gilch
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1 40225 Düsseldorf Germany
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg Albertstraße 21 79104 Freiburg Germany
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28
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Imran M, Taddei M, Sukhanov AA, Bussotti L, Ni W, Foggi P, Gurzadyan GG, Zhao J, Di Donato M, Voronkova VK. Radical-Enhanced Intersystem Crossing in Perylene-Oxoverdazyl Radical Dyads. Chemphyschem 2022; 23:e202100912. [PMID: 35191573 DOI: 10.1002/cphc.202100912] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Indexed: 11/07/2022]
Abstract
Linking stable radicals to organic chromophores is an effective method to enhance the intersystem crossing (ISC) of chromophores. Herein we prepared perylene-oxoverdazyl dyads either by directly connecting the two units or using an intervening phenyl spacer. We investigated the effect of the radical on the photophysical properties of perylene and observed strong fluorescence quenching due to radical enhanced intersystem crossing (REISC). Compared with a previously reported perylene fused nitroxide radical compound (triplet lifetime = 0.1 µs), these new adducts show a longer-lived triplet excited state (9.5 µs). Based on the singlet oxygen quantum yield (7%), we propose that the radical enhanced internal conversion also plays a role in the relaxation of the excited state. Femtosecond fluorescence up-conversion indicates a fast decay of the excited state (<1.0 ps), suggesting a strong spin-spin exchange interaction between the two units. Femtosecond transient absorption (fs-TA) spectra confirmed direct triplet state population (within 0.5 ps). Interestingly, by fs-TA, we observed the interconversion of the two states (D1/Q1) at ~80 ps time scale. Time-resolved electron paramagnetic resonance (TREPR) spectral study confirmed the formation of the quartet sate , we observed triplet and quartet states simultaneously with weights of 0.7 and 0.3, respectively. DFT computations showed that the interaction between radical and chromophore is ferromagnetic ( J >0, 0.05~0.10 eV).
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Affiliation(s)
- Muhammad Imran
- 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, Italy
| | - Andrey A Sukhanov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Kazan, 420029, Russia
| | - Laura Bussotti
- LENS (European Laboratory for Non-Linear Spectroscopy), Via N. Carrara 1, 50019, Sesto Fiorentino, Italy
| | - Wenjun Ni
- Institute of Artificial Photosynthesis, State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Ling-Gong Road, Dalian, 116024, P.R. China
| | - Paolo Foggi
- LENS (European Laboratory for Non-Linear Spectroscopy), Via N. Carrara 1, 50019, Sesto Fiorentino, Italy
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
| | - Gagik G Gurzadyan
- Institute of Artificial Photosynthesis, State Key Laboratory of Fine Chemicals, Dalian University of Technology, 2 Ling-Gong Road, Dalian, 116024, P.R. China
| | - 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
| | - Mariangela Di Donato
- LENS (European Laboratory for Non-Linear Spectroscopy), Via N. Carrara 1, 50019, Sesto Fiorentino, Italy
- ICCOM-CNR, Via Madonna del Piano 10, 50019, Sesto Fiorentino (FI), Italy
| | - Violeta K Voronkova
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Kazan, 420029, Russia
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29
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Tretyakov EV, Ovcharenko VI, Terent'ev AO, Krylov IB, Magdesieva TV, Mazhukin DG, Gritsan NP. Conjugated nitroxide radicals. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5025] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Minami N, Yoshida K, Maeguchi K, Kato K, Shimizu A, Kashima G, Fujiwara M, Uragami C, Hashimoto H, Teki Y. π-Topology and Ultrafast Excited-State Dynamics of Remarkably Photochemically Stabilized Pentacene Derivatives with Radical Substituents. Phys Chem Chem Phys 2022; 24:13514-13518. [DOI: 10.1039/d2cp00683a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pentacene derivatives with both π-radical- and TIPS-substituents (1m and 1p) were synthesized and their photochemical properties and excited-state dynamics were evaluated. The pentacene-radical-linked systems 1m (1p) showed a remarkable improvement...
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31
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Cao H, Kurganskii I, Pang J, Duan R, Zhao J, Fedin M, Li MD, Li C. Charge Transfer, Intersystem Crossing, and Electron Spin Dynamics in a Compact Perylenemonoimide-Phenoxazine Electron Donor-Acceptor Dyad. J Phys Chem B 2021; 125:12859-12875. [PMID: 34767365 DOI: 10.1021/acs.jpcb.1c08471] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
With phenoxazine (PXZ) as the electron donor and perylene-3,4-dicarboximide (PMI) as the electron acceptor, we prepared a compact, orthogonal electron donor-acceptor dyad (PMI-PXZ) to study the spin-orbit charge transfer-induced intersystem crossing (SOCT-ISC). A weak charge transfer (CT) absorption band, due to S0 → 1CT transition, was observed (ε = 2840 M-1 cm-1 at 554 nm, FWHM: 2850 cm-1), which is different from that of the previously reported analogue dyad with phenothiazine as the electron donor (PMI-PTZ), for which no CT absorption band was observed. A long-lived triplet state was observed (lifetime τT = 182 μs) with nanosecond transient absorption spectroscopy, and the singlet oxygen quantum yield (ΦΔ = 76%) is higher than that of the previously reported analogue dyad PMI-PTZ (ΦΔ = 57%). Ultrafast charge separation (ca. 0.14 ps) and slow charge recombination (1.4 ns) were observed with femtosecond transient absorption spectroscopy. With time-resolved electron paramagnetic resonance spectroscopy (TREPR), we confirmed the SOCT-ISC mechanism, and the electron spin polarization phase pattern of the triplet-state TREPR spectrum is (e, e, a, e, a, a), which is dramatically different from that of PMI-PTZ (a, e, a, e, a, e), indicating that the triplet-state TREPR spectrum of a specific chromophore in the electron donor-acceptor dyads is not only dependent on the geometry of the dyads but also dependent on the structure of the electron donor (or acceptor). Even one-atom variation in the donor structure may cause significant influence on the electron spin selectivity of the ISC of the electron donor-acceptor dyads.
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Affiliation(s)
- Huaiman Cao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Ivan Kurganskii
- International Tomography Center, SB RAS Institutskaya Str., 3A, Novosibirsk 630090, Russia
| | - Junhong Pang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, P. R. China
| | - Ruomeng Duan
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, Guangdong, P. R. China
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China
| | - Matvey Fedin
- International Tomography Center, SB RAS Institutskaya Str., 3A, Novosibirsk 630090, Russia
| | - Ming-De Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, P. R. China
| | - Chen Li
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, Guangdong, P. R. China
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32
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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.
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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
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33
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Kandrashkin YE, van der Est A. Enhanced Intersystem Crossing due to Resonant Energy Transfer to a Remote Spin. J Phys Chem Lett 2021; 12:7312-7318. [PMID: 34319743 DOI: 10.1021/acs.jpclett.1c02032] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A new mechanism for enhanced intersystem crossing in coupled three-spin systems consisting of a chromophore and an attached radical is proposed. It is shown that if the unpaired electron of the radical experiences spin-orbit coupling and different exchange interactions with the two unpaired electron spins of the chromophore, energy transfer from the chromophore to the radical can occur together with singlet-triplet intersystem crossing in the chromophore. The efficiency of this process increases dramatically when the electronic excitation of the radical is resonant with the S1-T1 energy gap of the chromophore. The types of systems in which this resonance could be achieved are discussed, and it is suggested that the mechanism could result in improved sensitization in near-IR emitting lanthanide dyes.
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Affiliation(s)
- Yuri E Kandrashkin
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Kazan 420029, Russian Federation
| | - Art van der Est
- Department of Chemistry Brock University, St. Catharines, ON L2S 3A1, Canada
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34
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Imran M, Zhang X, Wang Z, Chen X, Zhao J, Barbon A, Voronkova VK. Electron spin dynamics in excited state photochemistry: recent development in the study of intersystem crossing and charge transfer in organic compounds. Phys Chem Chem Phys 2021; 23:15835-15868. [PMID: 34318823 DOI: 10.1039/d1cp01937f] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Electron spin dynamics are crucial to photochemical and photophysical processes. However, to a large extent, they are neglected in routine photochemistry studies. Herein, we summarized the recent developments of electron spin dynamics in organic molecular systems. The electron-spin selective intersystem crossing (ISC) as well as charge separation (CS) and charge recombination (CR) of the organic molecular system are discussed, including ISC of the compounds with twisted π-conjugation frameworks and CR-induced ISC in compact orthogonal electron donor-acceptor dyads. We found that the electron spin polarization (ESP) of the triplet state formed in these systems is highly dependent on the molecular structure and geometry. The zero-field-splitting (ZFS) D and E parameters of the triplet state of series chromophores determined with time-resolved electron paramagnetic resonance (TREPR) spectroscopy are presented. Some unanswered questions in related areas are raised, which may inspire further theoretical investigations. The examples demonstrate that the study of electron spin dynamics is not only important in fundamental photochemistry to attain in-depth understanding of the ISC and the charge transfer processes, but is also useful for designing new efficient organic molecular materials for applications including photodynamic therapy, organic light-emitting diodes, and photon upconversion.
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Affiliation(s)
- Muhammad Imran
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, 2 Ling-Gong Road, Dalian, 116024, P. R. China.
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35
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Kandrashkin YE. Influence of Spin Decoherence on the Yield of Photodriven Quantum Teleportation in Molecular Triads. J Phys Chem Lett 2021; 12:6405-6410. [PMID: 34232670 DOI: 10.1021/acs.jpclett.1c01549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The evolution of spin coherences due to spin-selective recombination in the system with three unpaired electrons is discussed. It is shown that in the case of bidirectional kinetics, the decoherence processes can significantly change the quantum yield of the products. This enables one to discriminate between approaches that model spin-selective recombination but predict different decoherence rates. The rigid donor-acceptor-radical molecular triad is suggested to study the decay rate of singlet-triplet coherence. A modification of the photodriven quantum teleportation protocol is proposed to measure the quantum yields of the monoradical products.
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Affiliation(s)
- Yuri E Kandrashkin
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract 10/7, Kazan 420029, Russian Federation
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36
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Kusamoto T, Kimura S. Photostable Luminescent Triarylmethyl Radicals and Their Metal Complexes: Photofunctions Unique to Open-shell Electronic States. CHEM LETT 2021. [DOI: 10.1246/cl.210201] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Tetsuro Kusamoto
- Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Shonan Village, Hayama, Kanagawa 240-0193, Japan
- JST-PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Shun Kimura
- Institute for Molecular Science, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan
- Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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37
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Excited state dynamics and electron transfer in a phosphorus(V) porphyrin – TEMPO conjugate. J CHEM SCI 2021. [DOI: 10.1007/s12039-021-01925-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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38
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Deckers J, Cardeynaels T, Lutsen L, Champagne B, Maes W. Heavy-Atom-Free Bay-Substituted Perylene Diimide Donor-Acceptor Photosensitizers. Chemphyschem 2021; 22:1488-1496. [PMID: 34031956 DOI: 10.1002/cphc.202100269] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/10/2021] [Indexed: 11/05/2022]
Abstract
Perylene diimide (PDI) dyes are extensively investigated because of their favorable photophysical characteristics for a wide range of organic material applications. Fine-tuning of the optoelectronic properties is readily achieved by functionalization of the electron-deficient PDI scaffold. Here, we present four new donor-acceptor type dyads, wherein the electron donor units - benzo[1,2-b : 4,5-b']dithiophene, 9,9-dimethyl-9,10-dihydroacridine, dithieno[3,2-b : 2',3'-d]pyrrole, and triphenylamine-are attached to the bay-positions of the PDI acceptor. Intersystem crossing occurs for these systems upon photoexcitation, without the aid of heavy atoms, resulting in singlet oxygen quantum yields up to 80 % in toluene solution. Furthermore, this feature is retained when the system is directly irradiated with energy corresponding to the intramolecular charge-transfer absorption band (at 639 nm). Geometrical optimization and (time-dependent) density functional theory calculations afford more insights into the requirements for intersystem crossing such as spin-orbit coupling, dihedral angles, the involvement of charge-transfer states, and energy level alignment.
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Affiliation(s)
- Jasper Deckers
- UHasselt-Hasselt University, Institute for Materials Research (IMO), Design & Synthesis of Organic Semiconductors (DSOS), Agoralaan, 3590, Diepenbeek, Belgium.,IMEC, Associated Lab IMOMEC, Wetenschapspark 1, 3590, Diepenbeek, Belgium
| | - Tom Cardeynaels
- UHasselt-Hasselt University, Institute for Materials Research (IMO), Design & Synthesis of Organic Semiconductors (DSOS), Agoralaan, 3590, Diepenbeek, Belgium.,IMEC, Associated Lab IMOMEC, Wetenschapspark 1, 3590, Diepenbeek, Belgium.,UNamur-University of Namur, Laboratory of Theoretical Chemistry (LTC), Theoretical and Structural Physical Chemistry Unit, Namur Institute of Structured Matter, Rue de Bruxelles 61, 5000, Namur, Belgium
| | - Laurence Lutsen
- IMEC, Associated Lab IMOMEC, Wetenschapspark 1, 3590, Diepenbeek, Belgium
| | - Benoît Champagne
- UNamur-University of Namur, Laboratory of Theoretical Chemistry (LTC), Theoretical and Structural Physical Chemistry Unit, Namur Institute of Structured Matter, Rue de Bruxelles 61, 5000, Namur, Belgium
| | - Wouter Maes
- UHasselt-Hasselt University, Institute for Materials Research (IMO), Design & Synthesis of Organic Semiconductors (DSOS), Agoralaan, 3590, Diepenbeek, Belgium.,IMEC, Associated Lab IMOMEC, Wetenschapspark 1, 3590, Diepenbeek, Belgium
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39
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Mayländer M, Chen S, Lorenzo ER, Wasielewski MR, Richert S. Exploring Photogenerated Molecular Quartet States as Spin Qubits and Qudits. J Am Chem Soc 2021; 143:7050-7058. [PMID: 33929834 DOI: 10.1021/jacs.1c01620] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Photogenerated molecular spin systems hold great promise for applications in quantum information science because they can be prepared in well-defined spin states at modest temperatures, they often exhibit long coherence times, and their properties can be tuned by chemical synthesis. Here, we investigate a molecular spin system composed of a 1,6,7,12-tetra(4-tert-butylphenoxy)perylene-3,4:9,10-bis(dicarboximide) (PDI) chromophore covalently linked to a stable nitroxide radical (TEMPO) by optical and electron paramagnetic resonance (EPR) techniques. Upon photoexcitation of the spin system, a quartet state is formed as confirmed by transient nutation experiments. This quartet state has spin polarization lifetimes longer than 0.1 ms and is characterized by relatively long coherence times of ∼1.8 μs even at 80 K. Rabi oscillation experiments reveal that more than 60 single-qubit logic operations can be performed with this system at 80 K. The large magnitude of the nitroxide 14N hyperfine coupling in the quartet state of PDI-TEMPO is resolved in the transient EPR spectra and leads to a further splitting of the quartet state electron spin sublevels. We discuss the properties of this photogenerated multilevel system, comprising 12 electron-nuclear spin states, in the context of its viability as a qubit for applications in quantum information science.
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Affiliation(s)
- Maximilian Mayländer
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - Su Chen
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Emmaline R Lorenzo
- Department of Chemistry, Center for Molecular Quantum Transduction, and Institute for Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, 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, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104 Freiburg, Germany
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40
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Berger F, de Sousa JA, Zhao S, Zorn NF, El Yumin AA, Quintana García A, Settele S, Högele A, Crivillers N, Zaumseil J. Interaction of Luminescent Defects in Carbon Nanotubes with Covalently Attached Stable Organic Radicals. ACS NANO 2021; 15:5147-5157. [PMID: 33600164 PMCID: PMC7992189 DOI: 10.1021/acsnano.0c10341] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 02/05/2021] [Indexed: 05/17/2023]
Abstract
The functionalization of single-walled carbon nanotubes (SWCNTs) with luminescent sp3 defects has greatly improved their performance in applications such as quantum light sources and bioimaging. Here, we report the covalent functionalization of purified semiconducting SWCNTs with stable organic radicals (perchlorotriphenylmethyl, PTM) carrying a net spin. This model system allows us to use the near-infrared photoluminescence arising from the defect-localized exciton as a highly sensitive probe for the short-range interaction between the PTM radical and the SWCNT. Our results point toward an increased triplet exciton population due to radical-enhanced intersystem crossing, which could provide access to the elusive triplet manifold in SWCNTs. Furthermore, this simple synthetic route to spin-labeled defects could enable magnetic resonance studies complementary to in vivo fluorescence imaging with functionalized SWCNTs and facilitate the scalable fabrication of spintronic devices with magnetically switchable charge transport.
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Affiliation(s)
- Felix
J. Berger
- Institute
for Physical Chemistry, Universität
Heidelberg, 69120 Heidelberg, Germany
- Centre
for Advanced Materials, Universität
Heidelberg, 69120 Heidelberg, Germany
| | - J. Alejandro de Sousa
- Institut
de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain
- Laboratorio
de Electroquímica, Departamento de Química, Facultad
de Ciencias, Universidad de los Andes, 5101 Mérida, Venezuela
| | - Shen Zhao
- Faculty
of Physics, Munich Quantum Center and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, 80539 München, Germany
- Munich Center
for Quantum Science and Technology (MCQST), 80799 München, Germany
| | - Nicolas F. Zorn
- Institute
for Physical Chemistry, Universität
Heidelberg, 69120 Heidelberg, Germany
- Centre
for Advanced Materials, Universität
Heidelberg, 69120 Heidelberg, Germany
| | - Abdurrahman Ali El Yumin
- Institute
for Physical Chemistry, Universität
Heidelberg, 69120 Heidelberg, Germany
- Centre
for Advanced Materials, Universität
Heidelberg, 69120 Heidelberg, Germany
| | - Aleix Quintana García
- Institut
de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain
| | - Simon Settele
- Institute
for Physical Chemistry, Universität
Heidelberg, 69120 Heidelberg, Germany
| | - Alexander Högele
- Faculty
of Physics, Munich Quantum Center and Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, 80539 München, Germany
- Munich Center
for Quantum Science and Technology (MCQST), 80799 München, Germany
| | - Núria Crivillers
- Institut
de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain
| | - Jana Zaumseil
- Institute
for Physical Chemistry, Universität
Heidelberg, 69120 Heidelberg, Germany
- Centre
for Advanced Materials, Universität
Heidelberg, 69120 Heidelberg, Germany
- E-mail:
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41
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Nguyen VN, Yan Y, Zhao J, Yoon J. Heavy-Atom-Free Photosensitizers: From Molecular Design to Applications in the Photodynamic Therapy of Cancer. Acc Chem Res 2021; 54:207-220. [PMID: 33289536 DOI: 10.1021/acs.accounts.0c00606] [Citation(s) in RCA: 243] [Impact Index Per Article: 81.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Photodynamic therapy (PDT) is a clinically approved therapeutic modality that has shown great potential for the treatment of cancers owing to its excellent spatiotemporal selectivity and inherently noninvasive nature. However, PDT has not reached its full potential, partly due to the lack of ideal photosensitizers. A common molecular design strategy for effective photosensitizers is to incorporate heavy atoms into photosensitizer structures, causing concerns about elevated dark toxicity, short triplet-state lifetimes, poor photostability, and the potentially high cost of heavy metals. To address these drawbacks, a significant advance has been devoted to developing advanced smart photosensitizers without the use of heavy atoms to better fit the clinical requirements of PDT. Over the past few years, heavy-atom-free nonporphyrinoid photosensitizers have emerged as an innovative alternative class of PSs due to their superior photophysical and photochemical properties and lower expense. Heavy-atom-free nonporphyrinoid photosensitizers have been widely explored for PDT purposes and have shown great potential for clinical oncologic applications. Although many review articles about heavy-atom-free photosensitizers based on porphyrinoid structure have been published, no specific review articles have yet focused on the heavy-atom-free nonporphyrinoid photosensitizers.In this account, the specific concept related to heavy-atom-free photosensitizers and the advantageous properties of heavy-atom-free photosensitizers for cancer theranostics will be briefly introduced. In addition, recent progress in the development of heavy-atom-free photosensitizers, ranging from molecular design approaches to recent innovative types of heavy-atom-free nonporphyrinoid photosensitizers, emphasizing our own research, will be presented. The main molecular design approaches to efficient heavy-atom-free PSs can be divided into six groups: (1) the approach based on traditional tetrapyrrole structures, (2) spin-orbit charge-transfer intersystem crossing (SOCT-ISC), (3) reducing the singlet-triplet energy gap (ΔEST), (4) the thionation of carbonyl groups of conventional fluorophores, (5) twisted π-conjugation system-induced intersystem crossing, and (6) radical-enhanced intersystem crossing. The innovative types of heavy-atom-free nonporphyrinoid photosensitizers and their applications in cancer diagnostics and therapeutics will be discussed in detail in the third section. Finally, the challenges that need to be addressed to develop optimal heavy-atom-free photosensitizers for oncologic photodynamic therapy and a perspective in this research field will be provided. We believe that this review will provide general guidance for the future design of innovative photosensitizers and spur preclinical and clinical studies for PDT-mediated cancer treatments.
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Affiliation(s)
- Van-Nghia Nguyen
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
- Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam
| | - 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
| | - 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
| | - Juyoung Yoon
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, Korea
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42
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Nolden O, Fleck N, Lorenzo ER, Wasielewski MR, Schiemann O, Gilch P, Richert S. Excitation Energy Transfer and Exchange-Mediated Quartet State Formation in Porphyrin-Trityl Systems. Chemistry 2020; 27:2683-2691. [PMID: 32681763 PMCID: PMC7898503 DOI: 10.1002/chem.202002805] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Indexed: 01/07/2023]
Abstract
Photogenerated multi‐spin systems hold great promise for a range of technological applications in various fields, including molecular spintronics and artificial photosynthesis. However, the further development of these applications, via targeted design of materials with specific magnetic properties, currently still suffers from a lack of understanding of the factors influencing the underlying excited state dynamics and mechanisms on a molecular level. In particular, systematic studies, making use of different techniques to obtain complementary information, are largely missing. This work investigates the photophysics and magnetic properties of a series of three covalently‐linked porphyrin‐trityl compounds, bridged by a phenyl spacer. By combining the results from femtosecond transient absorption and electron paramagnetic resonance spectroscopies, we determine the efficiencies of the competing excited state reaction pathways and characterise the magnetic properties of the individual spin states, formed by the interaction between the chromophore triplet and the stable radical. The differences observed for the three investigated compounds are rationalised in the context of available theoretical models and the implications of the results of this study for the design of a molecular system with an improved intersystem crossing efficiency are discussed.
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Affiliation(s)
- Oliver Nolden
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Nico Fleck
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstraße 12, 53115, Bonn, Germany
| | - Emmaline R Lorenzo
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3113, USA
| | - Michael R Wasielewski
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208-3113, USA
| | - Olav Schiemann
- Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstraße 12, 53115, Bonn, Germany
| | - Peter Gilch
- Institute of Physical Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Sabine Richert
- Institute of Physical Chemistry, University of Freiburg, Albertstraße 21, 79104, Freiburg, Germany
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43
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Zhang X, Sukhanov AA, Yildiz EA, Kandrashkin YE, Zhao J, Yaglioglu HG, Voronkova VK. Radical‐Enhanced Intersystem Crossing in a Bay‐Substituted Perylene Bisimide−TEMPO Dyad and the Electron Spin Polarization Dynamics upon Photoexcitation**. Chemphyschem 2020; 22:55-68. [PMID: 33197104 DOI: 10.1002/cphc.202000861] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/13/2020] [Indexed: 01/15/2023]
Affiliation(s)
- Xue Zhang
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology E-208 West Campus, 2 Ling Gong Rd. Dalian 116024 China
| | - Andrey A. Sukhanov
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Elif Akhuseyin Yildiz
- Department of Engineering Physics Faculty of Engineering Ankara University 06100 Beşevler Ankara Turkey (H.G.Y
| | - Yuri E. Kandrashkin
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology E-208 West Campus, 2 Ling Gong Rd. Dalian 116024 China
| | - Halime Gul Yaglioglu
- Department of Engineering Physics Faculty of Engineering Ankara University 06100 Beşevler Ankara Turkey (H.G.Y
| | - Violeta K. Voronkova
- Zavoisky Physical-Technical Institute FRC Kazan Scientific Center of Russian Academy of Sciences Kazan 420029 Russia
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44
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Huang Y, Gong Q, Ge J, Tang P, Yu F, Xiao L, Wang Z, Sun H, Yu J, Li DS, Xiong Q, Zhang Q. Green Grinding-Coassembly Engineering toward Intrinsically Luminescent Tetracene in Cocrystals. ACS NANO 2020; 14:15962-15972. [PMID: 33112602 DOI: 10.1021/acsnano.0c07416] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Developing an effective and green method toward organic functional cocrystals based on the solubility-mismatched coformers is highly desirable and very important. Herein, we applied a green two-step liquid-assisted-grinding coassembly (LAGC) in fabricating tetracene-octafluoronaphthalene (TC-OFN) cocrystals from solubility-mismatched pairs of tetracene (TC, poorly soluble, 0.2 mg mL-1) and octafluoronaphthalene (OFN, highly soluble, 0.2 × 104 mg mL-1). Such cocrystals are extremely difficult to prepare through the common solution-processing strategies. More importantly, this two-step LAGC process could allow us to efficiently prepare TC-OFN cocrystals in gram scale. The as-prepared cocrystals displayed the intrinsic green emission of TC with much higher photoluminescence quantum yield (13.75%) comparing with the pure solid TC with the almost-quenched emission (0.41%, aggregation-caused quenching (ACQ)). The ultrafast spectra study on these cocrystals verifies the successful barrier function of OFN molecules in interrupting the well-known singlet fission (SF) in TC solids. Furthermore, this method can allow us to easily fabricate fluorescent TC-OFN water inks, which can be employed to prepare luminescent paintings or highly emissive ultratransparent/flexible films.
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Affiliation(s)
- Yinjuan Huang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Qiuyu Gong
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Jing Ge
- Division of Physics & Applied Physics, School of Physical and Mathematics Science, Nanyang Technological University, Singapore 639798, Singapore
| | - Pengpeng Tang
- Nanjing Tsinghe Environmental Protection Technology Co., Ltd, Nanjing, Jiangsu 210001, China
| | - Fei Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Lian Xiao
- Division of Physics & Applied Physics, School of Physical and Mathematics Science, Nanyang Technological University, Singapore 639798, Singapore
| | - Zongrui Wang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Handong Sun
- Division of Physics & Applied Physics, School of Physical and Mathematics Science, Nanyang Technological University, Singapore 639798, Singapore
| | - Jing Yu
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
| | - Dong-Sheng Li
- College of Materials and Chemical Engineering, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, China Three Gorges University, Yichang, Hubei 443002, China
| | - Qihua Xiong
- Division of Physics & Applied Physics, School of Physical and Mathematics Science, Nanyang Technological University, Singapore 639798, Singapore
| | - Qichun Zhang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore
- Department Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR 999077, China
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45
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Xiao X, Pang J, Sukhanov AA, Hou Y, Zhao J, Li MD, Voronkova VK. The effect of one-atom substitution on the photophysical properties and electron spin polarization: Intersystem crossing of compact orthogonal perylene/phenoxazine electron donor/acceptor dyad. J Chem Phys 2020; 153:184312. [PMID: 33187415 DOI: 10.1063/5.0023526] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A perylene (Pery)-phenoxazine (PXZ) compact orthogonal electron donor/acceptor dyad was prepared to study the relationship between the molecular structures and the spin-orbit charge transfer intersystem crossing (SOCT-ISC), as well as the electron spin selectivity of the ISC process. The geometry of Pery-PXZ (80.0°) is different from the previously reported perylene-phenothiazine dyad (Pery-PTZ, 91.5°), although there is only one atom variation for the two dyads. Pery-PXZ shows a high singlet oxygen quantum yield (84%). Femtosecond transient absorption spectra indicate that the charge separation (CS, faster than 120 fs) is faster than the Pery-PTZ analog (CS, 250 fs) and charge recombination (CR, i.e., SOCT-ISC, 5.98 ns) of Pery-PXZ is slower than the Pery-PTZ analog (CR, 0.9 ns). The intrinsic triplet state lifetime of Pery-PXZ is 242 µs vs the lifetime of 181 µs for the Pery-PTZ analog. Moreover, the triplet state lifetime of Pery-PXZ in the solid polymer matrix is extended to 4.45 ms, which indicates that the triplet state of Pery-PXZ in fluid solution is deactivated not only by the triplet-triplet annihilation effect but also by other factors such as vibration coupled relaxation. Interestingly, with pulsed laser excited time-resolved electron paramagnetic resonance spectroscopy, the electron spin polarization (ESP) pattern of the triplet state of the current dyad is opposite to that of Pery-PTZ. These results demonstrated the rich electron spin chemistry of the ISC of compact electron donor/acceptor dyads, e.g., the ESP is dependent on not only the molecular geometry but also the structure of the electron donor (or acceptor).
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Affiliation(s)
- Xiao Xiao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 West Campus, 2 Ling-Gong Road, Dalian 116024, People's Republic of China
| | - Junhong Pang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, People's Republic of China
| | - Andrei A Sukhanov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Kazan 420029, Russia
| | - Yuqi Hou
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, E-208 West Campus, 2 Ling-Gong Road, Dalian 116024, People's Republic of China
| | - 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, People's Republic of China
| | - Ming-De Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, People's Republic of China
| | - Violeta K Voronkova
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Kazan 420029, Russia
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46
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Xu Z, Huang Y, Cao Y, Jin T, Miller KA, Kaledin AL, Musaev DG, Lian T, Egap E. Enhanced intersystem crossing of boron dipyrromethene by TEMPO radical. J Chem Phys 2020; 153:154201. [PMID: 33092372 DOI: 10.1063/5.0025972] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Radical enhanced intersystem crossing (EISC) of organic chromophores is an important approach to generate a long-lived triplet state for various electronic and optoelectronic applications. However, structural factors and design rules to promote EISC are not entirely clear. In this work, we report a series of boron dipyrromethene (BODIPY) derivatives covalently linked with a 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) radical with varying distances and topologies. We show that the incorporation of the TEMPO radical to BODIPY results in strong fluorescence quenching by up to 85% as a result of EISC and enhanced internal conversion. In BDP-2AR [2-(4-methyleneamino-TEMPO) BODIPY], a dyad with the shortest BODIPY-TEMPO through-bond distance, we observe the fastest EISC rate (τisc = 1.4 ns) and the longest triplet excited state lifetime (τT = 32 µs) compared to other distance and geometry variations. Contrary to previous reports and a general presumption, the BODIPY-TEMPO through-bond distance in this system does not play a significant role on the triplet formation rate and yield. Density functional theory suggests a folding of the TEMPO radical to form a sandwich-like structure with a BODIPY ring that leads to a decrease in the through-space distance, providing a new and an interesting insight for the radical enhanced intersystem.
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Affiliation(s)
- Zihao Xu
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Yiming Huang
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Yulei Cao
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Tao Jin
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Kristen A Miller
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
| | - Alexey L Kaledin
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Djamaladdin G Musaev
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Tianquan Lian
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322, USA
| | - Eilaf Egap
- Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA
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47
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Wasielewski MR, Forbes MDE, Frank NL, Kowalski K, Scholes GD, Yuen-Zhou J, Baldo MA, Freedman DE, Goldsmith RH, Goodson T, Kirk ML, McCusker JK, Ogilvie JP, Shultz DA, Stoll S, Whaley KB. Exploiting chemistry and molecular systems for quantum information science. Nat Rev Chem 2020; 4:490-504. [PMID: 37127960 DOI: 10.1038/s41570-020-0200-5] [Citation(s) in RCA: 208] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2020] [Indexed: 12/21/2022]
Abstract
The power of chemistry to prepare new molecules and materials has driven the quest for new approaches to solve problems having global societal impact, such as in renewable energy, healthcare and information science. In the latter case, the intrinsic quantum nature of the electronic, nuclear and spin degrees of freedom in molecules offers intriguing new possibilities to advance the emerging field of quantum information science. In this Perspective, which resulted from discussions by the co-authors at a US Department of Energy workshop held in November 2018, we discuss how chemical systems and reactions can impact quantum computing, communication and sensing. Hierarchical molecular design and synthesis, from small molecules to supramolecular assemblies, combined with new spectroscopic probes of quantum coherence and theoretical modelling of complex systems, offer a broad range of possibilities to realize practical quantum information science applications.
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Affiliation(s)
| | - Malcolm D E Forbes
- Department of Chemistry, Bowling Green State University, Bowling Green, OH, USA
| | - Natia L Frank
- Department of Chemistry, University of Nevada-Reno, Reno, Nevada, USA
| | - Karol Kowalski
- Pacific Northwest National Laboratory, Richland, WA, USA
| | | | - Joel Yuen-Zhou
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Marc A Baldo
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Danna E Freedman
- Department of Chemistry, Northwestern University, Evanston, IL, USA
| | | | - Theodore Goodson
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Martin L Kirk
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM, USA
| | - James K McCusker
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | | | - David A Shultz
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
| | - Stefan Stoll
- Department of Chemistry, University of Washington, Seattle, WA, USA
| | - K Birgitta Whaley
- Department of Chemistry, University of California, Berkeley, CA, USA
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48
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Ten YA, Troshkova NM, Tretyakov EV. From spin-labelled fused polyaromatic compounds to magnetically active graphene nanostructures. RUSSIAN CHEMICAL REVIEWS 2020. [DOI: 10.1070/rcr4923] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Molecular design of magnetically active graphene nanoscale structures is an emerging field of research. The key goal of this research is to produce graphene nanoribbons and graphene quantum dots with specified electronic, optical and magnetic properties. The review considers methods for the synthesis of spin-labelled polycyclic aromatic hydrocarbons, which are homologous precursors of graphene nanostructures, and discusses the advances and prospects of the design of magnetically active graphene materials.
The bibliography includes 134 references.
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49
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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
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50
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Wang Z, Ivanov M, Gao Y, Bussotti L, Foggi P, Zhang H, Russo N, Dick B, Zhao J, Di Donato M, Mazzone G, Luo L, Fedin M. Spin–Orbit Charge‐Transfer Intersystem Crossing (ISC) in Compact Electron Donor–Acceptor Dyads: ISC Mechanism and Application as Novel and Potent Photodynamic Therapy Reagents. Chemistry 2020; 26:1091-1102. [DOI: 10.1002/chem.201904306] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/25/2019] [Indexed: 01/13/2023]
Affiliation(s)
- Zhijia Wang
- State Key Laboratory of Fine ChemicalsSchool of Chemical EngineeringDalian University of Technology E-208 West Campus, 2 Ling Gong Rd. Dalian 116024 P.R. China
| | - Mikhail Ivanov
- International Tomography CenterSB RAS Institutskaya Str. 3A, and Novosibirsk State University Pirogova str. 2 630090 Novosibirsk Russia
| | - Yuting Gao
- National Engineering Research Center for NanomedicineCollege of Life Science and TechnologyHuazhong University of Science and Technology Wuhan 430074 P.R. China
| | - Laura Bussotti
- LENS (European Laboratory for Non-Linear Spectroscopy) via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
| | - Paolo Foggi
- LENS (European Laboratory for Non-Linear Spectroscopy) via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
- Dipartimento di ChimicaUniversita di Perugia via Elce di Sotto 8 06123 Perugia Italy
| | - Huimin Zhang
- National Engineering Research Center for NanomedicineCollege of Life Science and TechnologyHuazhong University of Science and Technology Wuhan 430074 P.R. China
| | - Nino Russo
- Dipartimento di Chimica e Tecnologie ChimicheUniversità della Calabria 87036 Arcavacata di Rende Italy
| | - Bernhard Dick
- Lehrstuhl für Physikalische ChemieInstitut für Physikalische und Theoretische ChemieUniversität Regensburg Universitätsstrasse 31 93053 Regensburg Germany
| | - Jianzhang Zhao
- State Key Laboratory of Fine ChemicalsSchool of Chemical EngineeringDalian University of Technology E-208 West Campus, 2 Ling Gong Rd. Dalian 116024 P.R. China
| | - Mariangela Di Donato
- LENS (European Laboratory for Non-Linear Spectroscopy) via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
- INO, Istituto Nazionale di Ottica Largo Enrico Fermi 6 50125 Florence Italy
| | - Gloria Mazzone
- Dipartimento di Chimica e Tecnologie ChimicheUniversità della Calabria 87036 Arcavacata di Rende Italy
| | - Liang Luo
- National Engineering Research Center for NanomedicineCollege of Life Science and TechnologyHuazhong University of Science and Technology Wuhan 430074 P.R. China
| | - Matvey Fedin
- International Tomography CenterSB RAS Institutskaya Str. 3A, and Novosibirsk State University Pirogova str. 2 630090 Novosibirsk Russia
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