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Santoro A, Bella G, Cancelliere AM, Serroni S, Lazzaro G, Campagna S. Photoinduced Electron Transfer in Organized Assemblies—Case Studies. Molecules 2022; 27:molecules27092713. [PMID: 35566062 PMCID: PMC9102318 DOI: 10.3390/molecules27092713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 04/16/2022] [Accepted: 04/19/2022] [Indexed: 12/10/2022] Open
Abstract
In this review, photoinduced electron transfer processes in specifically designed assembled architectures have been discussed in the light of recent results reported from our laboratories. A convenient and useful way to study these systems is described to understand the rules that drive a light-induced charge-separated states and its subsequent decay to the ground state, also with the aim of offering a tutorial for young researchers. Assembled systems of covalent or supramolecular nature have been presented, and some functional multicomponent systems for the conversion of light energy into chemical energy have been discussed.
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2
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Huang G, Li J, Deng Z, Li J, Sun S, Xu L, Dang L, Li MD. Room-Temperature Stable Noncovalent Charge-Transfer Dianion Biradical to Produce Singlet Oxygen by Visible or Near-Infrared Light Photoexcitation. J Phys Chem Lett 2021; 12:4306-4312. [PMID: 33913708 DOI: 10.1021/acs.jpclett.1c00759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Noncovalent interaction between small molecules can generate a charge-transfer (CT) state, achieving the effect of a conjugated large molecule as well as a transition-metal complex. Herein, we demonstrate a room-temperature stable dianion biradical conveniently produced by noncovalent intermolecular CT interaction between anthraquinone (AQ) and potassium tert-butoxide (KOtBu). Essentially, CT from KOtBu to AQ boosts absorption bands from the UV to visible and near-infrared (NIR) range, enabling AQ-KOtBu to have new absorption bands around 400, 550, and 900 nm. The absorption bands of AQ-KOtBu are dramatically enhanced after blue-to-green or NIR light excitation. Interestingly, both ground state AQ-KOtBu (C(1)) and photoexcited AQ-KOtBu (C(2)) are quenched by oxygen to produce singlet oxygen. Furthermore, C(1) can be photoactivated by purged nitrogen in solution, and C(2) can be regenerated after the photoexcitation and purged nitrogen in solution, which may serve as a photosensitizer under visible and NIR light excitation.
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Affiliation(s)
- Guanheng Huang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Jiayu Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Ziqi Deng
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Jinghong Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Shanshan Sun
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Liang Xu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou 515031, P. R. China
| | - Li Dang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
| | - Ming-De Li
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structure Materials of Guangdong Providence, Shantou University, Shantou 515063, China
- Chemistry and Chemical Engineering Guangdong Laboratory, Shantou 515031, P. R. China
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3
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Wheeler D, Diodati AV, Tomlinson AL, Jeffries-EL M. Evaluating the Role of Molecular Heredity in the Optical and Electronic Properties of Cross-Conjugated Benzo[1,2- d:4,5- d']bisoxazoles. ACS OMEGA 2020; 5:12374-12384. [PMID: 32548421 PMCID: PMC7271376 DOI: 10.1021/acsomega.0c01126] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/08/2020] [Indexed: 06/11/2023]
Abstract
A series of eight benzo[1,2-d:4,5-d']bisoxazole (BBOs) were synthesized using the heredity principle as a design motif, whereby we investigated which characteristics of the linear parents were inherited by their cross-conjugated children. Four linear parents bearing 4-tert-butylbenzene (P) or 1,3-bis(4-tert-butylphenyl)benzene (M) at either the 2,6- or 4,8-position on the BBO and four cross-conjugated children bearing various combinations of the two isoelectronic aryl substituents were evaluated. Due to the bulky nature of the M substituent compared to that of the P substituent, the influence of steric hindrance along the BBO axes was explored theoretically and experimentally. The optical and electronic properties of each molecule were investigated in the solution and solid state using density functional theory (DFT) and time-dependent DFT (TD-DFT) and characterized using ultraviolet photoelectron spectroscopy (UPS), ultraviolet-visible (UV-vis) spectroscopy, and photoluminescence (PL) spectroscopy. The well-correlated theoretical and experimental results showed that the selective tuning of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels was possible through the strategic placement of substituents without impacting the H → L transition energy. Specifically, the theoretical results demonstrated that for the BBO children the HOMO and LUMO energy levels were inherited from the 4,8- and 2,6-parents, respectively. Each molecule was found to exhibit emission maxima ≤451 nm, making them ideal candidates for blue organic light-emitting diode (OLED) materials.
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Affiliation(s)
- David
L. Wheeler
- Department
of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
| | - Alex V. Diodati
- Department
of Chemistry and Biochemistry, University
of North Georgia, 82 College Circle, Dahlonega, Georgia 30041, United
States
- Department
of Chemistry, University of Florida, Leigh Hall, Gainesville, Florida 32603, United States
| | - Aimée L. Tomlinson
- Department
of Chemistry and Biochemistry, University
of North Georgia, 82 College Circle, Dahlonega, Georgia 30041, United
States
| | - Malika Jeffries-EL
- Department
of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States
- Division
of Materials Science and Engineering, Boston
University, 15 St. Mary
Street, Boston, Massachusetts 02215, United States
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4
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Tahara K, Koyama H, Fujitsuka M, Tokunaga K, Lei X, Majima T, Kikuchi JI, Ozawa Y, Abe M. Charge-Separated Mixed Valency in an Unsymmetrical Acceptor-Donor-Donor Triad Based on Diarylboryl and Triarylamine Units. J Org Chem 2019; 84:8910-8920. [PMID: 31072099 DOI: 10.1021/acs.joc.9b00836] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, we report the generation of new mixed-valence (MV) subspecies with charge-separated (CS) characters from an unsymmetrical acceptor-donor-donor (A-D-D) triad. The triad was synthesized by attaching a dimesitylboryl group (A) to a D-D conjugate that consisted of triarylamine (NAr3) units. The MV radical cation, obtained by chemical oxidation of the triad, exhibited a strong intervalence charge transfer (IVCT) absorption derived from the bis(NAr3)•+ moiety in the near-IR region. The charge-separated MV (CSMV) state, obtained by photoexcitation of the triad, caused a blue shift in IVCT energy in the femtosecond transient absorption spectra, reflecting a bias of positive charge distributions to the D end site. This resulted from increased electron density at the A site and restructuring of the central D site from NAr3 to NAr2 sites. Interestingly, any shift in the IVCT energy that was caused by the polarity of the solvent was minimal, reflecting the unique characteristics of the CSMV state. These findings represent the first detailed analysis of the CSMV state, including a comparison with conventional MV states. Therefore, this work provides new insights into counterion-free MV systems and their applications in molecular devices.
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Affiliation(s)
- Keishiro Tahara
- Department of Material Science and Research Center for New Functional Materials, Graduate School of Material Science , University of Hyogo , 3-2-1, Kouto , Kamigori, Ako , Hyogo 678-1297 , Japan
| | - Haruya Koyama
- Graduate School of Materials Science , Nara Institute of Science and Technology , 8916-5, Takayama , Ikoma, Nara 630-0192 , Japan
| | - Mamoru Fujitsuka
- Institute of Scientific and Industrial Research (SANKEN) , Osaka University , 8-1, Mihogaoka , Ibaraki , Osaka 567-0047 , Japan
| | - Ken Tokunaga
- Division of Liberal Arts, Centre for Promotion of Higher Education , Kogakuin University , 2665-1, Nakano , Hachioji, Tokyo 192-0015 , Japan
| | - Xu Lei
- Institute of Scientific and Industrial Research (SANKEN) , Osaka University , 8-1, Mihogaoka , Ibaraki , Osaka 567-0047 , Japan
| | - Tetsuro Majima
- Institute of Scientific and Industrial Research (SANKEN) , Osaka University , 8-1, Mihogaoka , Ibaraki , Osaka 567-0047 , Japan
| | - Jun-Ichi Kikuchi
- Graduate School of Materials Science , Nara Institute of Science and Technology , 8916-5, Takayama , Ikoma, Nara 630-0192 , Japan
| | - Yoshiki Ozawa
- Department of Material Science and Research Center for New Functional Materials, Graduate School of Material Science , University of Hyogo , 3-2-1, Kouto , Kamigori, Ako , Hyogo 678-1297 , Japan
| | - Masaaki Abe
- Department of Material Science and Research Center for New Functional Materials, Graduate School of Material Science , University of Hyogo , 3-2-1, Kouto , Kamigori, Ako , Hyogo 678-1297 , Japan
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5
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Kübel J, Wächtler M, Dietzek B. Excitation Power Modulates Energy-Transfer Dynamics in a Supramolecular Ru II -Fe II -Ru II Triad. Chemphyschem 2017; 18:2899-2907. [PMID: 28799732 DOI: 10.1002/cphc.201700710] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Indexed: 11/09/2022]
Abstract
Multichromophoric arrays are key to light harvesting in natural and artificial photosynthesis. A trinuclear, symmetric RuII -FeII -RuII triad may resemble a light-harvesting model system in which excitation energy from donor units (Ru-terpyridine fragments) is efficiently transferred to the acceptor (the Fe-terpyridine fragment). The photoinduced dynamics after simultaneous excitation of more than a single chromophoric unit (donor/acceptor) at varying excitation fluence is investigated in this contribution. Data suggests that energy transfer is decelerated if the acceptor states (on the FeII unit) are not depopulated fast enough. As a consequence, the lifetime of a high-lying excited state (centered on either of the RuII units) is prolonged. A kinetic model is suggested to account for this effect. Although the proposed model is specifically adopted to account for the experimental data reported here, it might be generalized to other situations in which multiple energy or electron donors are covalently linked to a single acceptor site, a situation of interest in contemporary artificial photosynthesis.
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Affiliation(s)
- Joachim Kübel
- Research Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT) Jena e.V., Albert-Einstein-Str. 9, 07745, Jena, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany.,Department of Chemistry and Molecular Biology, University of Gothenburg, 40530, Gothenburg, Sweden
| | - Maria Wächtler
- Research Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT) Jena e.V., Albert-Einstein-Str. 9, 07745, Jena, Germany
| | - Benjamin Dietzek
- Research Department Functional Interfaces, Leibniz Institute of Photonic Technology (IPHT) Jena e.V., Albert-Einstein-Str. 9, 07745, Jena, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University Jena, Helmholtzweg 4, 07743, Jena, Germany.,Center for Energy and Environmental Chemistry (CEEC), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
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6
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Solvent-control of photoinduced electron transfer via hydrogen bonding in a molecular triad made of a dinuclear chromophore subunit. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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7
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Wang L, Yin H, Jabed MA, Hetu M, Wang C, Monro S, Zhu X, Kilina S, McFarland SA, Sun W. π-Expansive Heteroleptic Ruthenium(II) Complexes as Reverse Saturable Absorbers and Photosensitizers for Photodynamic Therapy. Inorg Chem 2017; 56:3245-3259. [PMID: 28263079 DOI: 10.1021/acs.inorgchem.6b02624] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Five heteroleptic tris-diimine ruthenium(II) complexes [RuL(N^N)2](PF6)2 (where L is 3,8-di(benzothiazolylfluorenyl)-1,10-phenanthroline and N^N is 2,2'-bipyridine (bpy) (1), 1,10-phenanthroline (phen) (2), 1,4,8,9-tetraazatriphenylene (tatp) (3), dipyrido[3,2-a:2',3'-c]phenazine (dppz) (4), or benzo[i]dipyrido[3,2-a:2',3'-c]phenazine (dppn) (5), respectively) were synthesized. The influence of π-conjugation of the ancillary ligands (N^N) on the photophysical properties of the complexes was investigated by spectroscopic methods and simulated by density functional theory (DFT) and time-dependent DFT. Their ground-state absorption spectra were characterized by intense absorption bands below 350 nm (ligand L localized 1π,π* transitions) and a featureless band centered at ∼410 nm (intraligand charge transfer (1ILCT)/1π,π* transitions with minor contribution from metal-to-ligand charge transfer (1MLCT) transition). For complexes 4 and 5 with dppz and dppn ligands, respectively, broad but very weak absorption (ε < 800 M-1 cm-1) was present from 600 to 850 nm, likely emanating from the spin-forbidden transitions to the triplet excited states. All five complexes showed red-orange phosphorescence at room temperature in CH2Cl2 solution with decreased lifetimes and emission quantum yields, as the π-conjugation of the ancillary ligands increased. Transient absorption (TA) profiles were probed in acetonitrile solutions at room temperature for all of the complexes. Except for complex 5 (which showed dppn-localized 3π,π* absorption with a long lifetime of 41.2 μs), complexes 1-4 displayed similar TA spectral features but with much shorter triplet lifetimes (1-2 μs). Reverse saturable absorption (RSA) was demonstrated for the complexes at 532 nm using 4.1 ns laser pulses, and the strength of RSA decreased in the order: 2 ≥ 1 ≈ 5 > 3 > 4. Complex 5 is particularly attractive as a broadband reverse saturable absorber due to its wide optical window (430-850 nm) and long-lived triplet lifetime in addition to its strong RSA at 532 nm. Complexes 1-5 were also probed as photosensitizing agents for in vitro photodynamic therapy (PDT). Most of them showed a PDT effect, and 5 emerged as the most potent complex with red light (EC50 = 10 μM) and was highly photoselective for melanoma cells (selectivity factor, SF = 13). Complexes 1-5 were readily taken up by cells and tracked by their intracellular luminescence before and after a light treatment. Diagnostic intracellular luminescence increased with increased π-conjugation of the ancillary N^N ligands despite diminishing cell-free phosphorescence in that order. All of the complexes penetrated the nucleus and caused DNA condensation in cell-free conditions in a concentration-dependent manner, which was not influenced by the identity of N^N ligands. Although the mechanism for photobiological activity was not established, complexes 1-5 were shown to exhibit potential as theranostic agents. Together the RSA and PDT studies indicate that developing new agents with long intrinsic triplet lifetimes, high yields for triplet formation, and broad ground-state absorption to near-infrared (NIR) in tandem is a viable approach to identifying promising agents for these applications.
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Affiliation(s)
- Li Wang
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
| | - Huimin Yin
- Department of Chemistry, Acadia University , 6 University Avenue, Wolfville, NS B4P 2R6, Canada
| | - Mohammed A Jabed
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
| | - Marc Hetu
- Department of Chemistry, Acadia University , 6 University Avenue, Wolfville, NS B4P 2R6, Canada
| | - Chengzhe Wang
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
| | - Susan Monro
- Department of Chemistry, Acadia University , 6 University Avenue, Wolfville, NS B4P 2R6, Canada
| | - Xiaolin Zhu
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
| | - Svetlana Kilina
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
| | - Sherri A McFarland
- Department of Chemistry, Acadia University , 6 University Avenue, Wolfville, NS B4P 2R6, Canada.,Department of Chemistry and Biochemistry, University of North Carolina at Greensboro , Greensboro, North Carolina 27402-6170, United States
| | - Wenfang Sun
- Department of Chemistry and Biochemistry, North Dakota State University , Fargo, North Dakota 58108-6050, United States
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8
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Skaisgirski M, Guo X, Wenger OS. Electron Accumulation on Naphthalene Diimide Photosensitized by [Ru(2,2′-Bipyridine)3]2+. Inorg Chem 2017; 56:2432-2439. [DOI: 10.1021/acs.inorgchem.6b02446] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Michael Skaisgirski
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Xingwei Guo
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Oliver S. Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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9
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Yang GL, Zhao SF, Chen NY, Li S. Design and Syntheses of Novel Fluoroporphyrin-Anthraquinone Complexes as Antitumor Agents. Chem Pharm Bull (Tokyo) 2017; 64:1310-4. [PMID: 27581635 DOI: 10.1248/cpb.c16-00308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A novel fluoroporphyrin-anthraquinone hybrid with dipeptide link and its metal complexes were synthesized and evaluated for anti-proliferation activity in human cancer cell line HeLa. The preliminary results demonstrated that all the compounds showed moderate to excellent antitumor activities. Among the active compounds, compound 3 which contains fluorinated porphyrin-anthraquinone and zinc ion exhibited the highest potency with IC50 value of 8.83 µM, indicating that it was a promising antitumor candidate.
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Affiliation(s)
- Gu-Liang Yang
- Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization, College of Life Science, Huanggang Normal University
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10
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Kuss-Petermann M, Wenger OS. Pump-Pump-Probe Spectroscopy of a Molecular Triad Monitoring Detrimental Processes for Photoinduced Charge Accumulation. Helv Chim Acta 2016. [DOI: 10.1002/hlca.201600283] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Oliver S. Wenger
- Department of Chemistry; University of Basel; St. Johanns-Ring 19 CH-4056 Basel
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11
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Huang X, Webster RD, Harms K, Meggers E. Asymmetric Catalysis with Organic Azides and Diazo Compounds Initiated by Photoinduced Electron Transfer. J Am Chem Soc 2016; 138:12636-42. [DOI: 10.1021/jacs.6b07692] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xiaoqiang Huang
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Richard D. Webster
- Division
of Chemistry and Biological Chemistry, School of Physical and Mathematical
Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Klaus Harms
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Eric Meggers
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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12
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Orazietti M, Kuss‐Petermann M, Hamm P, Wenger OS. Lichtgetriebene Elektronenakkumulation in einer molekularen Pentade. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Margherita Orazietti
- Departement für ChemieUniversität Zürich Winterthurerstrasse 190 8057 Zürich Schweiz
| | | | - Peter Hamm
- Departement für ChemieUniversität Zürich Winterthurerstrasse 190 8057 Zürich Schweiz
| | - Oliver S. Wenger
- Departement für ChemieUniversität Basel St. Johanns-Ring 19 4056 Basel Schweiz
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13
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Orazietti M, Kuss-Petermann M, Hamm P, Wenger OS. Light-Driven Electron Accumulation in a Molecular Pentad. Angew Chem Int Ed Engl 2016; 55:9407-10. [PMID: 27336756 DOI: 10.1002/anie.201604030] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Indexed: 11/10/2022]
Abstract
Accumulation and temporary storage of redox equivalents with visible light as an energy input is of pivotal importance for artificial photosynthesis because key reactions, such as CO2 reduction or water oxidation, require the transfer of multiple redox equivalents. We report on the first purely molecular system, in which a long-lived charge-separated state (τ≈870 ns) with two electrons accumulated on a suitable acceptor unit can be observed after excitation with visible light. Importantly, no sacrificial reagents were employed.
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Affiliation(s)
- Margherita Orazietti
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Martin Kuss-Petermann
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Peter Hamm
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.
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14
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Kuss-Petermann M, Wenger OS. Unusual distance dependences of electron transfer rates. Phys Chem Chem Phys 2016; 18:18657-64. [DOI: 10.1039/c6cp03124b] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
There are regimes in which electron transfer rates increase with increasing donor–acceptor distance, leading to rate maxima at large donor–acceptor separations.
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