1
|
Lv K, Zhang M, Xia X, Liu W, Wan K, Zhang M, Li F. Cyano modified triphenylmethyl radical skeletons: higher stability and efficiency. Chem Commun (Camb) 2024; 60:4846-4849. [PMID: 38619487 DOI: 10.1039/d4cc00903g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
We introduced cyano groups to replace chlorine atoms in the tris(2,4,6-trichlorophenyl)methyl (TTM) radical skeleton, resulting in two cyano-modified TTM skeletons. The incorporation of cyano groups effectively suppresses nonradiative transition processes and lowers the frontier molecular orbital energy levels compared to those of the TTM radical. Consequently, enhanced photoluminescence quantum efficiency (PLQE) and a shift towards longer-wavelength emission in solution were achieved. Furthermore, the cyano-modified TTM skeletons exhibited improved stabilities. The development of these two skeletons adds diversity to stable organic luminescent radical skeletons.
Collapse
Affiliation(s)
- Kuo Lv
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Minzhe Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Xin Xia
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Wenjing Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Keke Wan
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Ming Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China.
| |
Collapse
|
2
|
Ju CW, Shen Y, French EJ, Yi J, Bi H, Tian A, Lin Z. Accurate Electronic and Optical Properties of Organic Doublet Radicals Using Machine Learned Range-Separated Functionals. J Phys Chem A 2024. [PMID: 38382058 DOI: 10.1021/acs.jpca.3c07437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Luminescent organic semiconducting doublet-spin radicals are unique and emergent optical materials because their fluorescent quantum yields (Φfl) are not compromised by the spin-flipping intersystem crossing (ISC) into a dark high-spin state. The multiconfigurational nature of these radicals challenges their electronic structure calculations in the framework of single-reference density functional theory (DFT) and introduces room for method improvement. In the present study, we extended our earlier development of ML-ωPBE [J. Phys. Chem. Lett., 2021, 12, 9516-9524], a range-separated hybrid (RSH) exchange-correlation (XC) functional constructed using the stacked ensemble machine learning (SEML) algorithm, from closed-shell organic semiconducting molecules to doublet-spin organic semiconducting radicals. We assessed its performance for a new test set of 64 doublet-spin radicals from five categories while placing all previously compiled 3926 closed-shell molecules in the new training set. Interestingly, ML-ωPBE agrees with the nonempirical OT-ωPBE functional regarding the prediction of the molecule-dependent range-separation parameter (ω), with a small mean absolute error (MAE) of 0.0197 a0-1, but saves the computational cost by 2.46 orders of magnitude. This result demonstrates an outstanding domain adaptation capacity of ML-ωPBE for diverse organic semiconducting species. To further assess the predictive power of ML-ωPBE in experimental observables, we also applied it to evaluate absorption and fluorescence energies (Eabs and Efl) using linear-response time-dependent DFT (TDDFT), and we compared its behavior with nine popular XC functionals. For most radicals, ML-ωPBE reproduces experimental measurements of Eabs and Efl with small MAEs of 0.299 and 0.254 eV, only marginally different from those of OT-ωPBE. Our work illustrates a successful extension of the SEML framework from closed-shell molecules to doublet-spin radicals and will open the venue for calculating optical properties for organic semiconductors using single-reference TDDFT.
Collapse
Affiliation(s)
- Cheng-Wei Ju
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
| | - Yili Shen
- Manning College of Information and Computer Sciences, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Ethan J French
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Department of Mathematics and Statistics, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, United States
| | - Jun Yi
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Hongshan Bi
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Aaron Tian
- Manning College of Information and Computer Sciences, University of Massachusetts, Amherst, Massachusetts 01003, United States
- Department of Mathematics and Statistics, University of Massachusetts, Amherst, Massachusetts 01003, United States
| | - Zhou Lin
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, United States
| |
Collapse
|
3
|
Yang Y, Qiu L, Shi X. Chalcogen Effect of Atom Substitution on the Properties of Tris(2,4,6-trichlorophenyl)methyl(TTM) Radical. Chem Res Chin Univ 2023. [DOI: 10.1007/s40242-023-3008-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
|
4
|
Alcón I, Ribas-Ariño J, Moreira IDPR, Bromley ST. Emergent Spin Frustration in Neutral Mixed-Valence 2D Conjugated Polymers: A Potential Quantum Materials Platform. J Am Chem Soc 2023; 145:5674-5683. [PMID: 36877195 PMCID: PMC10021012 DOI: 10.1021/jacs.2c11185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
Two-dimensional conjugated polymers (2DCPs)─organic 2D materials composed of arrays of carbon sp2 centers connected by π-conjugated linkers─are attracting increasing attention due to their potential applications in device technologies. This interest stems from the ability of 2DCPs to host a range of correlated electronic and magnetic states (e.g., Mott insulators). Substitution of all carbon sp2 centers in 2DCPs by nitrogen or boron results in diamagnetic insulating states. Partial substitution of C sp2 centers by B or N atoms has not yet been considered for extended 2DCPs but has been extensively studied in the analogous neutral mixed-valence molecular systems. Here, we employ accurate first-principles calculations to predict the electronic and magnetic properties of a new class of hexagonally connected neutral mixed-valence 2DCPs in which every other C sp2 nodal center is substituted by either a N or B atom. We show that these neutral mixed-valence 2DCPs significantly energetically favor a state with emergent superexchange-mediated antiferromagnetic (AFM) interactions between C-based spin-1/2 centers on a triangular sublattice. These AFM interactions are surprisingly strong and comparable to those in the parent compounds of cuprate superconductors. The rigid and covalently linked symmetric triangular AFM lattice in these materials thus provides a highly promising and robust basis for 2D spin frustration. As such, extended mixed-valence 2DCPs are a highly attractive platform for the future bottom-up realization of a new class of all-organic quantum materials, which could host exotic correlated electronic states (e.g., unusual magnetic ordering, quantum spin liquids).
Collapse
Affiliation(s)
- Isaac Alcón
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - Jordi Ribas-Ariño
- Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTC), Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Ibério de P R Moreira
- Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTC), Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Stefan T Bromley
- Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTC), Universitat de Barcelona, c/ Martí i Franquès 1-11, 08028 Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain
| |
Collapse
|
5
|
Li X, Tan W, Bai X, Li F. Stable Near-infrared-emitting Radical Nanoparticles for Fluorescence Imaging. Chem Res Chin Univ 2023. [DOI: 10.1007/s40242-023-2365-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
|
6
|
Fluorescent Organic π‐Radicals Stabilized with Boron: Featuring a SOMO–LUMO Electronic Transition. Angew Chem Int Ed Engl 2022; 61:e202201965. [DOI: 10.1002/anie.202201965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Indexed: 11/07/2022]
|
7
|
Ito M, Shirai S, Xie Y, Kushida T, Ando N, Soutome H, Fujimoto KJ, Yanai T, Tabata K, Miyata Y, Kita H, Yamaguchi S. Fluorescent Organic π‐Radicals Stabilized with Boron: Featuring a SOMO–LUMO Electronic Transition. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Masato Ito
- Nagoya University: Nagoya Daigaku Graduate School of Science JAPAN
| | - Shusuke Shirai
- Nagoya University: Nagoya Daigaku Graduate School of Science JAPAN
| | - Yongfa Xie
- Nagoya University: Nagoya Daigaku Graduate School of Science JAPAN
| | | | - Naoki Ando
- Nagoya University: Nagoya Daigaku Graduate School of Science JAPAN
| | - Hiroki Soutome
- Nagoya University: Nagoya Daigaku Graduate School of Science JAPAN
| | - Kazuhiro J. Fujimoto
- Nagoya University: Nagoya Daigaku Institute of Transformative Bio-Molecules JAPAN
| | - Takeshi Yanai
- Nagoya University: Nagoya Daigaku Institute of Transformative Bio-Molecules JAPAN
| | | | | | | | - Shigehiro Yamaguchi
- Nagoya University Department of Chemistry Graduate School of Science Furo, Chikusa 464-8602 Nagoya JAPAN
| |
Collapse
|
8
|
Tanaka Y, Takahashi H, Akita M. Estimation of Electron Distribution over Dinuclear Organometallic Molecular Wires by "IR Tag" Analysis of Ancillary Acyl-Cp Ligands. ACS ORGANIC & INORGANIC AU 2022; 2:327-342. [PMID: 36855590 PMCID: PMC9955175 DOI: 10.1021/acsorginorgau.2c00005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding the details of electronic properties of mixed-valence (MV) states of organometallic molecular wires is essential to gain insights into electron transfer phenomena. Although the field of MV chemistry is matured, there remain issues to be solved, which cannot be accessed by the conventional analytical methods. Here, we describe the synthesis and properties of diruthenium bridging (diethynylbenzene)diyl wires, (μ-p and m-C≡C-C6H4-C≡C){RuCpR(dppe)}2 1, with the acyl-substituted cyclopentadienyl rings [CpR: Cpe; η5-C5H4COOMe (a-series: ester derivatives), Cpa; η5-C5H4COMe (b-series: acetyl derivatives)], which are installed as IR-tags to estimate electron densities at the metal centers in the MV species. The electrochemical and IR/near IR-spectroelectrochemical studies reveal that the two metal centers in the para-isomers p-1a,b + interact with each other more strongly than those in the meta-isomers m-1a,b + . Electron-spin resonance study also supports the radicals being delocalized over the Ru-(p-C≡C-C6H4-C≡C)-Ru moieties in p-1a,b + . The spectroelectrochemical IR study shows significant higher-energy shifts of the ν(C=O) vibrations brought about upon 1e-oxidation. Spectral simulation on the basis of the Bloch equations allows us to determine the electron transfer rate constants (k et) between the two metal centers being in the orders of 1012 s-1 ( p-1 + ) and 109 s-1 ( m-1 + ). The shifts of the ν(C=O) bands reveal that the charge densities on the para-isomers p-1a,b + are widely delocalized over the Ru-(p-C≡C-C6H4-C≡C)-Ru linkages in contrast to the meta-isomers m-1a,b + , where the electron densities are mainly localized on the metal fragments, as supported by the density functional theory and time-dependent density functional theory studies as well as comparison with the reference mononuclear acetylide complexes, C6H5-C≡C-RuCpR(dppe) 2. We have successfully demonstrated that the carbonyl groups (>C=O) in the ancillary Cp ligands also work as IR-tags to report detailed information on the electron densities at the metal centers and the electron distribution over MV complexes as well.
Collapse
Affiliation(s)
- Yuya Tanaka
- Laboratory
for Chemistry and Life Science, Institute
of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan,
| | - Hiroki Takahashi
- Department
of Chemical Science and Engineering, School of Materials and Chemical
Technology, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan
| | - Munetaka Akita
- Laboratory
for Chemistry and Life Science, Institute
of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta,
Midori-ku, Yokohama 226-8503, Japan,
| |
Collapse
|
9
|
Luo J, Rong XF, Ye YY, Li WZ, Wang XQ, Wang W. Research Progress on Triarylmethyl Radical-Based High-Efficiency OLED. Molecules 2022; 27:1632. [PMID: 35268732 PMCID: PMC8911689 DOI: 10.3390/molecules27051632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 11/17/2022] Open
Abstract
Perchlorotrityl radical (PTM), tris (2,4,6-trichlorophenyl) methyl radical (TTM), (3,5-dichloro-4-pyridyl) bis (2,4,6 trichlorophenyl) methyl radical (PyBTM), (N-carbazolyl) bis (2,4,6-trichlorophenyl) methyl radical (CzBTM), and their derivatives are stable organic radicals that exhibit light emissions at room temperature. Since these triarylmethyl radicals have an unpaired electron, their electron spins at the lowest excited state and ground state are both doublets, and the transition from the lowest excited state to the ground state does not pose the problem of a spin-forbidden reaction. When used as OLED layers, these triarylmethyl radicals exhibit unique light-emitting properties, which can increase the theoretical upper limit of the OLED's internal quantum efficiency (IQE) to 100%. In recent years, research on the luminescent properties of triarylmethyl radicals has attracted increasing attention. In this review, recent developments in these triarylmethyl radicals and their derivatives in OLED devices are introduced.
Collapse
Affiliation(s)
| | | | | | | | - Xiao-Qiang Wang
- College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (J.L.); (X.-F.R.); (Y.-Y.Y.); (W.-Z.L.)
| | - Wenjing Wang
- College of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (J.L.); (X.-F.R.); (Y.-Y.Y.); (W.-Z.L.)
| |
Collapse
|
10
|
Tan Y, Hsu SN, Tahir H, Dou L, Savoie BM, Boudouris BW. Electronic and Spintronic Open-Shell Macromolecules, Quo Vadis? J Am Chem Soc 2022; 144:626-647. [PMID: 34982552 DOI: 10.1021/jacs.1c09815] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Open-shell macromolecules (i.e., polymers containing radical sites either along their backbones or at the pendant sites of repeat units) have attracted significant attention owing to their intriguing chemical and physical (e.g., redox, optoelectronic, and magnetic) properties, and they have been proposed and/or implemented in a wide range of potential applications (e.g., energy storage devices, electronic systems, and spintronic modules). These successes span multiple disciplines that range from advanced macromolecular chemistry through nanoscale structural characterization and on to next-generation solid-state physics and the associated devices. In turn, this has allowed different scientific communities to expand the palette of radical-containing polymers relatively quickly. However, critical gaps remain on many fronts, especially regarding the elucidation of key structure-property-function relationships that govern the underlying electrochemical, optoelectronic, and spin phenomena in these materials systems. Here, we highlight vital developments in the history of open-shell macromolecules to explain the current state of the art in the field. Moreover, we provide a critical review of the successes and bring forward open opportunities that, if solved, could propel this class of materials in a meaningful manner. Finally, we provide an outlook to address where it seems most likely that open-shell macromolecules will go in the coming years. Our considered view is that the future of radical-containing polymers is extremely bright and the addition of talented researchers with diverse skills to the field will allow these materials and their end-use devices to have a positive impact on the global science and technology enterprise in a relatively rapid manner.
Collapse
Affiliation(s)
- Ying Tan
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States
| | - Sheng-Ning Hsu
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States
| | - Hamas Tahir
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States
| | - Letian Dou
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States.,Birck Nanotechnology Center, Purdue University, 1205 West State Street, West Lafayette, Indiana 47907, United States
| | - Brett M Savoie
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States
| | - Bryan W Boudouris
- Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States.,Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
| |
Collapse
|
11
|
Breimaier S, Winter RF. Electrochemical and Spectroscopic Studies on Triarylamine‐Polychlorotriphenylmethyl Dyads with Particularly Strong Triarylamine Donors. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Stefanie Breimaier
- Department of Chemistry University of Konstanz Universitätsstraße 10 78457 Konstanz Germany
| | - Rainer F. Winter
- Department of Chemistry University of Konstanz Universitätsstraße 10 78457 Konstanz Germany
| |
Collapse
|
12
|
Abdurahman A, Hele TJH, Gu Q, Zhang J, Peng Q, Zhang M, Friend RH, Li F, Evans EW. Understanding the luminescent nature of organic radicals for efficient doublet emitters and pure-red light-emitting diodes. NATURE MATERIALS 2020; 19:1224-1229. [PMID: 32541936 DOI: 10.1038/s41563-020-0705-9] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
The doublet-spin nature of radical emitters is advantageous for applications in organic light-emitting diodes, as it avoids the formation of triplet excitons that limit the electroluminescence efficiency of non-radical emitters. However, radicals generally show low optical absorption and photoluminescence yields. Here we explain the poor optical properties of radicals based on alternant hydrocarbons, and establish design rules to increase the absorption and luminescence yields for donor-acceptor-type radicals. We show that non-alternant systems are necessary to lift the degeneracy of the lowest energy orbital excitations; moreover, intensity borrowing from an intense high-lying transition by the low-energy charge-transfer excitation enhances the oscillator strength of the emitter. We apply these rules to design tris(2,4,6-trichlorophenyl)methyl-pyridoindolyl derivatives with a high photoluminescence quantum yield (>90%). Organic light-emitting diodes based on these molecules showed a pure-red emission with an over 12% external quantum efficiency. These insights may be beneficial for the rational design and discovery of highly luminescent doublet emitters.
Collapse
Affiliation(s)
- Alim Abdurahman
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
| | | | - Qinying Gu
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Jiangbin Zhang
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Qiming Peng
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
- Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University, Nanjing, P. R. China
| | - Ming Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China
| | | | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, P. R. China.
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| | - Emrys W Evans
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| |
Collapse
|
13
|
An K, Xie G, Gong S, Chen Z, Zhou X, Ni F, Yang C. Monoradically luminescent polymers by a super acid-catalyzed polymerization and deep-red electroluminescence. Sci China Chem 2020. [DOI: 10.1007/s11426-020-9778-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
14
|
Gu Q, Abdurahman A, Friend RH, Li F. Polymer Light Emitting Diodes with Doublet Emission. J Phys Chem Lett 2020; 11:5638-5642. [PMID: 32573241 DOI: 10.1021/acs.jpclett.0c01399] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Organic light-emitting radicals have developed rapidly due to their unique doublet emission and great potential in display technology. Although some organic light-emitting diodes (OLEDs) exploiting small-molecular radicals as the emitters have been reported, there is no report about the polymer-radical-based OLEDs until now. Herein, a kind of polymer radical, PS-CzTTM, is adopted as the emitter to fabricate solution-processed OLEDs. A maximum external quantum efficiency of 3.0% is achieved for a deep-red device with an emissive layer of PS-CzTTM lightly doped in 2,2',2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1H-benzimidazole) (TPBi). Temperature-dependent time-resolved photoluminescent spectra and transient electroluminescence of radical emitters and devices are first measured. The results demonstrate that the emission channels for both thin films and devices are from the transition of doublet excitons, indicating that the unique doublet emission mechanism of radicals is maintained in PS-CzTTM films and PS-CzTTM-based OLEDs.
Collapse
Affiliation(s)
- Qinying Gu
- Department of Physics, Cavendish Laboratory, Cambridge University, Cambridge CB3 0HF, U.K
| | - Alim Abdurahman
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, 2699 Changchun, P. R. China
| | - Richard H Friend
- Department of Physics, Cavendish Laboratory, Cambridge University, Cambridge CB3 0HF, U.K
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, 2699 Changchun, P. R. China
| |
Collapse
|
15
|
Efficient radical-based light-emitting diodes with doublet emission. Nature 2018; 563:536-540. [DOI: 10.1038/s41586-018-0695-9] [Citation(s) in RCA: 299] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 10/02/2018] [Indexed: 11/08/2022]
|
16
|
Cui Z, Ye S, Wang L, Guo H, Obolda A, Dong S, Chen Y, Ai X, Abdurahman A, Zhang M, Wang L, Li F. Radical-Based Organic Light-Emitting Diodes with Maximum External Quantum Efficiency of 10.6. J Phys Chem Lett 2018; 9:6644-6648. [PMID: 30398056 DOI: 10.1021/acs.jpclett.8b03019] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A new luminescent radical, tris-2,4,6-trichlorophenylmethyl-1,5-diazarcarbazole (TTM-DACz), was synthesized and characterized. The photoluminescence quantum yield of TTM-DACz in solid 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene matrix film (5 wt %) is as high as 57.0%. Organic light-emitting diodes (OLEDs) employing TTM-DACz as the emitter were fabricated. By rational design of the device structure and host-guest doping system, external quantum efficiency (EQE) of up to 10.6% of the optimized device with a red CIE chromaticity of (0.62, 0.36) was obtained, which is among the highest values for red OLEDs using nonphosphorescent materials as the emitters. This work will accelerate the development of luminescent radical materials for high-performance OLEDs.
Collapse
Affiliation(s)
- Zhiyuan Cui
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Shaofeng Ye
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , P.R. China
| | - Lu Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Haoqing Guo
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Ablikim Obolda
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Shengzhi Dong
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Yingxin Chen
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Xin Ai
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Alim Abdurahman
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Ming Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| | - Lei Wang
- Wuhan National Laboratory for Optoelectronics , Huazhong University of Science and Technology , Wuhan 430074 , P.R. China
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Avenue 2699 , Changchun 130012 , P.R. China
| |
Collapse
|
17
|
Diez-Cabanes V, Seber G, Franco C, Bejarano F, Crivillers N, Mas-Torrent M, Veciana J, Rovira C, Cornil J. Design of Perchlorotriphenylmethyl (PTM) Radical-Based Compounds for Optoelectronic Applications: The Role of Orbital Delocalization. Chemphyschem 2018; 19:2572-2578. [DOI: 10.1002/cphc.201800321] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Valentín Diez-Cabanes
- Laboratory for Chemistry of Novel Materials; University of Mons; Place du Parc 20 7000 Mons Belgium
| | - Gonca Seber
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Carlos Franco
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
- Current affiliation: ETH Zurich; Vladimir-Prelog-Weg 1-5/10 8093 Zurich Switzerland
| | - Francesc Bejarano
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Nuria Crivillers
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Marta Mas-Torrent
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Jaume Veciana
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Concepció Rovira
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC); Campus Universitari de UAB; 08193 Cerdanyola del Vallès (Barcelona) Spain
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel Materials; University of Mons; Place du Parc 20 7000 Mons Belgium
| |
Collapse
|
18
|
Dong S, Xu W, Guo H, Yan W, Zhang M, Li F. Effects of substituents on luminescent efficiency of stable triaryl methyl radicals. Phys Chem Chem Phys 2018; 20:18657-18662. [DOI: 10.1039/c8cp01492b] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The factors affecting the photoluminescence quantum yields (PLQYs) of perchlorotriphenyl methyl (PTM) and tris(2,4,6-trichlorophenyl)methyl (TTM) radical derivatives were studied systematically for the first time.
Collapse
Affiliation(s)
- Shengzhi Dong
- State Key Laboratory of Supramolecular Structure and Materials
- College of Chemistry
- Jilin University
- Changchun
- P. R. China
| | - Wei Xu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- P. R. China
| | - Haoqing Guo
- State Key Laboratory of Supramolecular Structure and Materials
- College of Chemistry
- Jilin University
- Changchun
- P. R. China
| | - Wenfu Yan
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- College of Chemistry
- Jilin University
- Changchun 130012
- P. R. China
| | - Ming Zhang
- State Key Laboratory of Supramolecular Structure and Materials
- College of Chemistry
- Jilin University
- Changchun
- P. R. China
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials
- College of Chemistry
- Jilin University
- Changchun
- P. R. China
| |
Collapse
|
19
|
Han J, Jiang Y, Obolda A, Duan P, Li F, Liu M. Doublet-Triplet Energy Transfer-Dominated Photon Upconversion. J Phys Chem Lett 2017; 8:5865-5870. [PMID: 29144138 DOI: 10.1021/acs.jpclett.7b02677] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Stable luminescent π-radicals with doublet emission have aroused a growing interest for functional molecular materials. We have demonstrated a neutral π-radical dye (4-N-carbazolyl-2,6-dichlorophenyl)bis(2,4,6-trichlorophenyl)-methyl (TTM-1Cz) with remarkable doublet emission, which could be used as triplet sensitizer to initiate the photophysical process of triplet-triplet annihilation photon upconversion (TTA-UC). Dexter-like excited doublet-triplet energy transfer (DTET) was confirmed by theoretical calculation. With the same sensitizer, a mixed solution of TTM-1Cz and aromatic emitters could upconvert red light (λ = 635 nm) to blue or cyan light. An anti-Stokes energy shift as large as 0.92 eV was observed from red to blue light upconversion. This finding of DTET phenomena offers a new kind of triplet sensitizer for TTA-UC.
Collapse
Affiliation(s)
- Jianlei Han
- Division of Nanophotonics, CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST) , No. 11 ZhongGuanCun BeiYiTiao, 100190 Beijing, People's Republic of China
| | - Yuqian Jiang
- Division of Nanophotonics, CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST) , No. 11 ZhongGuanCun BeiYiTiao, 100190 Beijing, People's Republic of China
| | - Ablikim Obolda
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Qianjin Avenue 2699, Changchun, 130012, People's Republic of China
| | - Pengfei Duan
- Division of Nanophotonics, CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST) , No. 11 ZhongGuanCun BeiYiTiao, 100190 Beijing, People's Republic of China
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University , Qianjin Avenue 2699, Changchun, 130012, People's Republic of China
| | - Minghua Liu
- Division of Nanophotonics, CAS Center for Excellence in Nanoscience, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology (NCNST) , No. 11 ZhongGuanCun BeiYiTiao, 100190 Beijing, People's Republic of China
- Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences , No. 2 ZhongGuanCun BeiYiJie, 100190, Beijing, People's Republic of China
| |
Collapse
|
20
|
Chen L, Mallick S, Tan YN, Meng M, Liu CY. Charge Transfer Properties of Triarylamine Integrated Dimolybdenum Dyads. Inorg Chem 2017. [PMID: 28636342 DOI: 10.1021/acs.inorgchem.7b00913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Three quadruply bonded dimolybdenum complexes equipped with a triarylamine pendant, [(DAniF)3Mo2(μ-O2CC6H4N(C6H4CH3)2] (DAniF = N,N'-di(p-anisyl)formamidinate; [OO-ph-N]), [(DAniF)3Mo2(μ-OSCC6H4N(C6H4CH3)2] ([OS-ph-N]), and [(DAniF)3Mo2(μ-S2CC6H4N(C6H4CH3)2] ([SS-ph-N]), have been synthesized and characterized by single crystal X-ray diffraction. In electrochemical measurements, the redox couple for the organic amine group becomes irreversible, reflecting the substantially strong electronic interaction between the dimetal center and organic redox site. The potential difference for the two successive redox events, ca. ΔE1/2(E1/2(2)(N/N•+) - E1/2(1)(Mo2IV/V)), falls in the range of 0.5-0.8 V as estimated from the differential pulse voltammograms. For the monocation radicals [OO-ph-N]+, [OS-ph-N]+, and [SS-ph-N]+, obtained by chemical oxidation of the neutral precursor, a broad ligand (amine) to metal (Mo2) charge transfer (LMCT) absorption band is observed in the near-IR region. Interestingly, analogous to the intervalence charge transfer (IVCT) bands for mixed-valence complexes, the LMCT absorption bands, which are solvent dependent, decrease in energy and bandwidth as the electronic coupling between the two redox sites increases in an order of increasing S content in the chelating group. The electronic coupling matrix elements (Hab) are determined by optical analyses from the generalized Mulliken-Hush (GMH) theory, falling in the range of 400-800 cm-1 in CH2Cl2. These results indicate that in these radical cations the charge is localized. Time-dependent DFT calculations show that the frontier molecular orbitals for these asymmetrical donor-acceptor systems have unbalanced distribution of electron density, and the LMCT bands arise from an electronic transition from the pendant ligand-based to metal-based molecular orbitals, corresponding to donor (N)-acceptor (Mo2) charge transfer.
Collapse
Affiliation(s)
- Lu Chen
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Suman Mallick
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Ying Ning Tan
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Miao Meng
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| | - Chun Y Liu
- Department of Chemistry, Jinan University , 601 Huang-Pu Avenue West, Guangzhou-510632, China
| |
Collapse
|
21
|
Wu X, Kim JO, Medina S, Ramírez FJ, Mayorga Burrezo P, Wu S, Lim ZL, Lambert C, Casado J, Kim D, Wu J. Push-Pull-Type Polychlorotriphenylmethyl Radicals: New Two-Photon Absorbers and Dyes for Generation of Photo-Charges. Chemistry 2017; 23:7698-7702. [DOI: 10.1002/chem.201701875] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Xiaojin Wu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials; Nanjing Tech University; Nanjing 211816 P. R. China
- Department of Chemistry, National; University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
| | - Jun Oh Kim
- Department of Chemistry; Yonsei University; Seoul 120-749 Korea
| | - Samara Medina
- Department of Physical Chemistry; University of Malaga; Campus de Teatinos s/n 229071 Malaga Spain
| | - Francisco J. Ramírez
- Department of Physical Chemistry; University of Malaga; Campus de Teatinos s/n 229071 Malaga Spain
| | - Paula Mayorga Burrezo
- Department of Physical Chemistry; University of Malaga; Campus de Teatinos s/n 229071 Malaga Spain
| | - Shaofei Wu
- Department of Chemistry, National; University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
| | - Zheng Long Lim
- Department of Chemistry, National; University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
| | - Christoph Lambert
- Institut für Organische Chemie; Universität Würzburg; Am Hubland 97074 Würzburg Germany
| | - Juan Casado
- Department of Physical Chemistry; University of Malaga; Campus de Teatinos s/n 229071 Malaga Spain
| | - Dongho Kim
- Department of Chemistry; Yonsei University; Seoul 120-749 Korea
| | - Jishan Wu
- Department of Chemistry, National; University of Singapore; 3 Science Drive 3 Singapore 117543 Singapore
| |
Collapse
|
22
|
Evolution of emission manners of organic light-emitting diodes: From emission of singlet exciton to emission of doublet exciton. CHINESE CHEM LETT 2016. [DOI: 10.1016/j.cclet.2016.06.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
23
|
Obolda A, Peng Q, He C, Zhang T, Ren J, Ma H, Shuai Z, Li F. Triplet-Polaron-Interaction-Induced Upconversion from Triplet to Singlet: a Possible Way to Obtain Highly Efficient OLEDs. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:4740-4746. [PMID: 27028509 DOI: 10.1002/adma.201504601] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 02/04/2016] [Indexed: 06/05/2023]
Abstract
Two D-A-type molecules, 4-N-[4-(9-phenylcarbazole)]-3,5-bis(4-diphenylamine)phenyl-4H-1,2,4-triazole and 4,4'-(9-(4-(1-phenyl-1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-9H-carbazole-3,6-diyl) bis-(N,N-diphenylaniline), are designed and synthesized. Organic lightemitting diodes based on them exhibit deep-blue emission and the singlet formation ratios are higher than the simple spin-statistics of 25%. A triplet-polaroninteraction-induced upconversion from triplet to singlet through a one-electron transfer mechanism is proposed, and is proven by magnetocurrent measurement and quantum-chemistry computation.
Collapse
Affiliation(s)
- Ablikim Obolda
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China
| | - Qiming Peng
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China
| | - Chuanyou He
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China
| | - Tian Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Jiajun Ren
- Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Hongwei Ma
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China
| | - Zhigang Shuai
- Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Qianjin Avenue, Changchun, 130012, P. R. China
| |
Collapse
|
24
|
Zhong YW, Gong ZL, Shao JY, Yao J. Electronic coupling in cyclometalated ruthenium complexes. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.01.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
25
|
Pfaff U, Hildebrandt A, Korb M, Oßwald S, Linseis M, Schreiter K, Spange S, Winter RF, Lang H. Electronically Strongly Coupled Divinylheterocyclic-Bridged Diruthenium Complexes. Chemistry 2016; 22:783-801. [PMID: 26660031 DOI: 10.1002/chem.201503687] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Indexed: 11/12/2022]
Abstract
Complexes [{Ru(CO)Cl(PiPr3 )2 }2 (μ-2,5-(CH-CH)2 -(c) C4 H2 E] (E=NR; R=C6 H4 -4-NMe2 (10 a), C6 H4 -4-OMe (10 b), C6 H4 -4-Me (10 c), C6 H5 (10 d), C6 H4 -4-CO2 Et (10 e), C6 H4 -4-NO2 (10 f), C6 H3 -3,5-(CF3 )2 (10 g), CH3 (11); E=O (12), S (13)) are discussed. The solid state structures of four alkynes and two complexes are reported. (Spectro)electrochemical studies show a moderate influence of the nature of the heteroatom and the electron-donating or -withdrawing substituents R in 10 a-g on the electrochemical and spectroscopic properties. The CVs display two consecutive one-electron redox events with ΔE°'=350-495 mV. A linear relationship between ΔE°' and the σp Hammett constant for 10 a-f was found. IR, UV/Vis/NIR and EPR studies for 10(+) -13(+) confirm full charge delocalization over the {Ru}CH-CH-heterocycle-CH-CH{Ru} backbone, classifying them as Class III systems according to the Robin and Day classification. DFT-optimized structures of the neutral complexes agree well with the experimental ones and provide insight into the structural consequences of stepwise oxidations.
Collapse
Affiliation(s)
- Ulrike Pfaff
- Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany)
| | - Alexander Hildebrandt
- Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany)
| | - Marcus Korb
- Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany)
| | - Steffen Oßwald
- Faculty of Chemistry, Universität Konstanz, 78457 Konstanz (Germany)
| | - Michael Linseis
- Faculty of Chemistry, Universität Konstanz, 78457 Konstanz (Germany)
| | - Katja Schreiter
- Faculty of Natural Sciences, Institute of Chemistry, Polymer Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany)
| | - Stefan Spange
- Faculty of Natural Sciences, Institute of Chemistry, Polymer Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany)
| | - Rainer F Winter
- Faculty of Chemistry, Universität Konstanz, 78457 Konstanz (Germany).
| | - Heinrich Lang
- Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, Technische Universität Chemnitz, 09107 Chemnitz (Germany).
| |
Collapse
|
26
|
Braunschweig H, Krummenacher I, Mailänder L, Pentecost L, Vargas A. Formation of a stable radical by oxidation of a tetraorganoborate. Chem Commun (Camb) 2016; 52:7005-8. [DOI: 10.1039/c6cc02916g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxidation of a tetraorganoborate salt leads to selective formation of the corresponding zwitterionic radical rather than carbon–carbon bond formation of the boron substituents.
Collapse
Affiliation(s)
- Holger Braunschweig
- Institut für Anorganische Chemie
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Lisa Mailänder
- Institut für Anorganische Chemie
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Leanne Pentecost
- Department of Chemistry
- School of Life Sciences
- University of Sussex
- Brighton BN1 9QJ
- UK
| | - Alfredo Vargas
- Department of Chemistry
- School of Life Sciences
- University of Sussex
- Brighton BN1 9QJ
- UK
| |
Collapse
|
27
|
Shen JJ, Shao JY, Zhu X, Zhong YW. Amine–Amine Electronic Coupling through a Dibenzo[a,e]pentalene Bridge. Org Lett 2015; 18:256-9. [PMID: 26720697 DOI: 10.1021/acs.orglett.5b03408] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Jun-Jian Shen
- Beijing National Laboratory
for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Beijing 100190, China
| | - Jiang-Yang Shao
- Beijing National Laboratory
for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Beijing 100190, China
| | - Xiaozhang Zhu
- Beijing National Laboratory
for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Beijing 100190, China
| | - Yu-Wu Zhong
- Beijing National Laboratory
for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, 2 Bei Yi Jie, Zhong Guan Cun, Beijing 100190, China
| |
Collapse
|
28
|
Peng Q, Obolda A, Zhang M, Li F. Organic Light-Emitting Diodes Using a Neutral π Radical as Emitter: The Emission from a Doublet. Angew Chem Int Ed Engl 2015; 54:7091-5. [DOI: 10.1002/anie.201500242] [Citation(s) in RCA: 225] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Revised: 04/07/2015] [Indexed: 11/10/2022]
|
29
|
Peng Q, Obolda A, Zhang M, Li F. Organic Light-Emitting Diodes Using a Neutral π Radical as Emitter: The Emission from a Doublet. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500242] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
30
|
Steeger M, Griesbeck S, Schmiedel A, Holzapfel M, Krummenacher I, Braunschweig H, Lambert C. On the relation of energy and electron transfer in multidimensional chromophores based on polychlorinated triphenylmethyl radicals and triarylamines. Phys Chem Chem Phys 2015; 17:11848-67. [DOI: 10.1039/c4cp05929h] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chromophores with many donors and acceptors show electron transfer which is identical to energy transfer.
Collapse
Affiliation(s)
- Markus Steeger
- Institut für Organische Chemie
- Universität Würzburg, and Center for Nanosystems Chemistry
- 97074 Würzburg
- Germany
| | - Stefanie Griesbeck
- Institut für Organische Chemie
- Universität Würzburg, and Center for Nanosystems Chemistry
- 97074 Würzburg
- Germany
| | - Alexander Schmiedel
- Institut für Organische Chemie
- Universität Würzburg, and Center for Nanosystems Chemistry
- 97074 Würzburg
- Germany
| | - Marco Holzapfel
- Institut für Organische Chemie
- Universität Würzburg, and Center for Nanosystems Chemistry
- 97074 Würzburg
- Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie
- Universität Würzburg
- 97074 Würzburg
- Germany
| | | | - Christoph Lambert
- Institut für Organische Chemie
- Universität Würzburg, and Center for Nanosystems Chemistry
- 97074 Würzburg
- Germany
| |
Collapse
|
31
|
Winter RF. Half-Wave Potential Splittings ΔE1/2 as a Measure of Electronic Coupling in Mixed-Valent Systems: Triumphs and Defeats. Organometallics 2014. [DOI: 10.1021/om500029x] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Rainer F. Winter
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| |
Collapse
|
32
|
Fajarí L, Papoular R, Reig M, Brillas E, Jorda JL, Vallcorba O, Rius J, Velasco D, Juliá L. Charge Transfer States in Stable Neutral and Oxidized Radical Adducts from Carbazole Derivatives. J Org Chem 2014; 79:1771-7. [DOI: 10.1021/jo4028215] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Lluís Fajarí
- Departament de Quı́mica Biològica i Modelització
Molecular, Institut de Quı́mica Avançada de Catalunya (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Robert Papoular
- Laboratoire Leon Brillouin, IRAMIS, CEA-Saclay, 91191 Gif-sur-Yvette, France
| | - Marta Reig
- Departament de Quı́mica
Orgànica Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, Martí Franquès 1-11, 08028 Barcelona, Spain
| | - Enric Brillas
- Departament de Quı́mica
Fı́sica, Universitat de Barcelona, Martí Franquès 1-11, 08028 Barcelona, Spain
| | - José Luis Jorda
- Instituto de Tecnología Quı́mica (UPV-CSIC), Av. de los
Naranjos s/n, 46022 Valencia, Spain
| | - Oriol Vallcorba
- Institut de Ciència de Materials (CSIC), Campus
de la U.A.B., 08193 Bellaterra, Spain
| | - Jordi Rius
- Institut de Ciència de Materials (CSIC), Campus
de la U.A.B., 08193 Bellaterra, Spain
| | - Dolores Velasco
- Departament de Quı́mica
Orgànica Institut de Nanociència i Nanotecnologia (IN2UB), Universitat de Barcelona, Martí Franquès 1-11, 08028 Barcelona, Spain
| | - Luis Juliá
- Departament de Quı́mica Biològica i Modelització
Molecular, Institut de Quı́mica Avançada de Catalunya (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain
| |
Collapse
|
33
|
Polit W, Mücke P, Wuttke E, Exner T, Winter RF. Charge and Spin Confinement to the Amine Site in 3-Connected Triarylamine Vinyl Ruthenium Conjugates. Organometallics 2013. [DOI: 10.1021/om4007455] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Walther Polit
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Philipp Mücke
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Evelyn Wuttke
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Thomas Exner
- Pharmazeutisches
Institut, Eberhard-Karls Universität Tübingen, Auf
der Morgenstelle 8, D-72076 Tübingen, Germany
| | - Rainer F. Winter
- Fachbereich
Chemie, Universität Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| |
Collapse
|
34
|
Palladium-Catalyzed sp2 C–N Bond Forming Reactions: Recent Developments and Applications. TOP ORGANOMETAL CHEM 2012. [DOI: 10.1007/3418_2012_56] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
35
|
Heckmann A, Lambert C. Organic Mixed-Valence Compounds: A Playground for Electrons and Holes. Angew Chem Int Ed Engl 2011; 51:326-92. [DOI: 10.1002/anie.201100944] [Citation(s) in RCA: 414] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Indexed: 11/05/2022]
|
36
|
Heckmann A, Lambert C. Organische gemischtvalente Verbindungen: ein Spielplatz für Elektronen und Löcher. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201100944] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
37
|
Hildebrandt A, Schaarschmidt D, Claus R, Lang H. Influence of Electron Delocalization in Heterocyclic Core Systems on the Electrochemical Communication in 2,5-Di- and 2,3,4,5-Tetraferrocenyl Thiophenes, Furans, and Pyrroles. Inorg Chem 2011; 50:10623-32. [DOI: 10.1021/ic200926z] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alexander Hildebrandt
- Department of Chemistry, Chair Inorganic Chemistry, Chemnitz University of Technology, Strasse der Nationen 62, 09111 Chemnitz, Germany
| | - Dieter Schaarschmidt
- Department of Chemistry, Chair Inorganic Chemistry, Chemnitz University of Technology, Strasse der Nationen 62, 09111 Chemnitz, Germany
| | - Ron Claus
- Department of Chemistry, Chair Inorganic Chemistry, Chemnitz University of Technology, Strasse der Nationen 62, 09111 Chemnitz, Germany
| | - Heinrich Lang
- Department of Chemistry, Chair Inorganic Chemistry, Chemnitz University of Technology, Strasse der Nationen 62, 09111 Chemnitz, Germany
| |
Collapse
|
38
|
Mandal S, Parida KN, Samanta S, Moorthy JN. Influence of (2,3,4,5,6-Pentamethyl/phenyl)phenyl Scaffold: Stereoelectronic Control of the Persistence of o-Quinonoid Reactive Intermediates of Photochromic Chromenes. J Org Chem 2011; 76:7406-14. [DOI: 10.1021/jo201144t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Susovan Mandal
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | | | - Subhas Samanta
- Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India
| | | |
Collapse
|
39
|
Mücke P, Linseis M, Záliš S, Winter RF. Vinyl-ruthenium entities as markers for intramolecular electron transfer processes. Inorganica Chim Acta 2011. [DOI: 10.1016/j.ica.2011.03.071] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
40
|
Affiliation(s)
- Jihane Hankache
- Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammannstrasse 4, D-37077 Göttingen, Germany
| | | |
Collapse
|
41
|
Kaupp M, Renz M, Parthey M, Stolte M, Würthner F, Lambert C. Computational and spectroscopic studies of organic mixed-valence compounds: where is the charge? Phys Chem Chem Phys 2011; 13:16973-86. [DOI: 10.1039/c1cp21772k] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
42
|
Renz M, Theilacker K, Lambert C, Kaupp M. A reliable quantum-chemical protocol for the characterization of organic mixed-valence compounds. J Am Chem Soc 2010; 131:16292-302. [PMID: 19831383 DOI: 10.1021/ja9070859] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Structures, dipole moments, electron-transfer barriers, and spin density distributions of a series of mixed-valent bistriarylamin radical cations have been studied systematically by hybrid density functional methods with variable exact-exchange admixture combined with a continuum solvent model. The chosen systems differ in their bridging units and are all relatively close, from both sides, to the class II/III borderline of the Robin-Day classification of mixed-valence systems. Solvent effects are found to have a dramatic influence on the localized vs delocalized character of these cations. While gas-phase calculations or computations in a nonpolar solvent place all systems on the delocalized class III side, a more polar solvent like acetonitrile enables observation of symmetry breaking and charge localization with moderate exact-exchange admixtures in a hybrid functional for the systems on the class II side (with diphenylbutadiyne and diphenylethyne bridges). In contrast, the cations with the shortest bridges (phenylene, biphenylene) are characterized as class III. The comparison of computed intervalence charge-transfer excitation frequencies with experiment confirms the system with the diphenylbutadiyne bridge, and probably the system with the diphenylethyne bridge, to be class II, whereas in the dichloromethane solvent employed for spectroscopic measurements, the two other systems are on the class III side. Nonstandard hybrid density functional calculations with 35% Hartree-Fock-like exchange combined with continuum solvent models are suggested as a practical protocol for the quantum-chemical characterization of organic mixed-valence systems. This approach should allow closer examinations and provides a basis for the evaluation of other computational methods.
Collapse
Affiliation(s)
- Manuel Renz
- Institut für Anorganische Chemie, Universität Würzburg, Germany
| | | | | | | |
Collapse
|
43
|
Grisanti L, D’Avino G, Painelli A, Guasch J, Ratera I, Veciana J. Essential State Models for Solvatochromism in Donor−Acceptor Molecules: The Role of the Bridge. J Phys Chem B 2009; 113:4718-25. [DOI: 10.1021/jp809771d] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Luca Grisanti
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| | - Gabriele D’Avino
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| | - Anna Painelli
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| | - Judith Guasch
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| | - Imma Ratera
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| | - Jaume Veciana
- Dipartimento Chimica GIAF, Parma University, and INSTM-UdR Parma, I-43100 Parma, Italy, and Institut de Ciéncia de Materials de Barcelona (CSIC)/CIBER-BBN, Campus Univ. Bellaterra, 08193-Cerdanyola, Barcelona, Spain
| |
Collapse
|
44
|
Zhou G, Baumgarten M, Müllen K. Arylamine-Substituted Oligo(ladder-type pentaphenylene)s: Electronic Communication between Bridged Redox Centers. J Am Chem Soc 2007; 129:12211-21. [PMID: 17880071 DOI: 10.1021/ja073148s] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Novel bis(arylamine-substituted) oligo(ladder-type pentaphenylene)s 1-3, with bridge lengths estimated to be 2.2, 4.2, and 6.3 nm, respectively, have been developed, and the model compound 4 with a mono-arylamine substituent was also synthesized. Their absorption spectra in different solvents are almost identical, while distinct bathochromic shifts of the photoluminescence (PL) spectra were observed with increasing solvent polarity due to the polarized excited states. The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) spectra display a two-step oxidation of the bridged diamines in compound 1, which suggests that the electron and charge delocalize in mixed-valence (MV) cation 1+* and that both redox centers can communicate through the pentaphenylene bridge. Only unresolved curves in CV and DPV spectra were observed in the first two oxidation processes of diamines 2 and 3, indicating that the bridges are too long for efficient delocalization over the entire molecules and the radical cations localize at each arylamine center. This finding was further supported by chemical oxidation with SbCl5 and studies of the corresponding UV-vis-NIR absorption spectra of compounds 1-4. A significant intervalence charge-transfer (IVCT) band around 5283 cm-1 (1893 nm) was observed in 1+*. This is the first report of such a highly intense IVCT band in the NIR region with intensity similar to that of the visible band of the radicals, enabling further analysis of the CT process and the coupling matrix element V, classifying 1+* as a class II derivative (V = 1.6 kcal/mol). This study may offer an effective way to improve the understanding of charge transfer and charge-carrier transport in various conjugated oligomers or polymers and facilitate their ongoing exploration in optoelectronic applications.
Collapse
Affiliation(s)
- Gang Zhou
- Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
| | | | | |
Collapse
|
45
|
Ratera I, Sporer C, Ruiz-Molina D, Ventosa N, Baggerman J, Brouwer AM, Rovira C, Veciana J. Solvent Tuning from Normal to Inverted Marcus Region of Intramolecular Electron Transfer in Ferrocene-Based Organic Radicals. J Am Chem Soc 2007; 129:6117-29. [PMID: 17451238 DOI: 10.1021/ja066351g] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The solvent dependence of spectroscopic data of two neutral paramagnetic donor-acceptor dyads, based on a polychlorinated triphenylmethyl radical acceptor unit linked through a vinylene pi-bridge to a ferrocene (compound 1) or a nonamethylferrocene donor (compound 2) unit, is described. Both compounds exhibit broad absorptions in the near-IR region, with band maxima appearing around 1000 and 1500 nm for 1 and 2, respectively. These bands correspond to the excitation of a neutral DA ground state to the charge-separated D+A- state, indicative of an intramolecular electron-transfer process. Compounds 1 and 2 show two reversible one-electron redox processes associated with the oxidation of the ferrocene and the reduction of the polychlorotriphenylmethyl radical subunits. The solvent dependence of the redox potentials was also investigated, allowing the determination of the redox asymmetries DeltaG degrees of both dyads. The latter values, along with the experimental Eopt spectroscopic data, allow us to estimate, using the total energy balance Eopt = lambda + DeltaG degrees , the reorganization energy values, lambda, and their solvent polarity dependence. Since DeltaG degrees and lambda are of the same order of magnitude but exhibit opposite trends in their solvent polarity dependence, a unique shift from the normal to the inverted Marcus region with the change in solvent polarity is found. The kinetics of the charge recombination step of the excited charge-separated D+A- state was studied by picosecond transient absorption spectroscopy, which allows us to observe and monitor for the first time the charge-separated D+A- state, thereby confirming unambiguously the photoinduced electron-transfer phenomena.
Collapse
Affiliation(s)
- Imma Ratera
- Institut de Ciència de Materials de Barcelona, Campus Universitari de Ballaterra, 08193 Bellaterra, Catalonia, Spain
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Heckmann A, Lambert C. Neutral Organic Mixed-Valence Compounds: Synthesis and All-Optical Evaluation of Electron-Transfer Parameters. J Am Chem Soc 2007; 129:5515-27. [PMID: 17407287 DOI: 10.1021/ja068235j] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this paper we present the synthesis as well as a detailed study of the electrochemical and photophysical properties of a series of neutral organic mixed-valence (MV) compounds, 1-7, in which different amine donor centers are connected to perchlorinated triarylmethyl radical units by various spacers. We show that this new class of compounds are excellent model systems for the investigation of electron transfer due to their uncharged character and, consequently, their excellent solubility, particularly in nonpolar solvents. A detailed band shape analysis of the intervalence charge-transfer (IV-CT) bands in the context of Jortner's theory allowed the electron-transfer parameters (inner vibrational reorganization energy lambdav, outer solvent reorganization energy lambdao, and the difference in the free energy between the diabatic ground and excited states, DeltaG degrees degrees , as well as the averaged molecular vibrational mode v) to be extracted independently. In this way we were able to analyze the solvatochromic behavior of the IV-CT bands by evaluating the contribution of each parameter. By comparison of different compounds, we were also able to assign specific molecular moieties to changes in vv. For this class of molecules, we also demonstrate that the adiabatic dipole moment difference Deltamicroab and, consequently, the electronic coupling V12 can be evaluated directly from the absorption spectra by a new variant of the solvatochromic method. Furthermore, an investigation of the electrochemistry of compounds 1-7 by cyclic voltammetry as well as spectroelectrochemistry shows that, not only in the neutral MV compounds but also in their oxidized forms, a charge transfer can be optically induced but with exchanged donor-acceptor functionalities of the redox centers.
Collapse
Affiliation(s)
- Alexander Heckmann
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | | |
Collapse
|
47
|
Amthor S, Lambert C. Dications of Bis-triarylamino-[2.2]paracyclophanes: Evaluation of Excited State Couplings by GMH Analysis. J Phys Chem A 2006; 110:3495-504. [PMID: 16526628 DOI: 10.1021/jp055098o] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this paper, we present the absorption properties of a series of bis-triarylamino-[2.2]paracyclophane diradical dications. The localized pi-pi and the charge-transfer (CT) transitions of these dications are explained and analyzed by an exciton coupling model that also considers the photophysical properties of the "monomeric" triarylamine radical cations. Together with AM1-CISD-calculated transition moments, experimental transition moments and transition energies of the bis-triarylamine dications were used to calculate electronic couplings by a generalized Mulliken-Hush (GMH) approach. These couplings are a measure for interactions of the excited mixed-valence CT states. The modification of the diabatic states reveals similarities of the GMH three-level model and the exciton coupling model. Comparison of the two models shows that the transition moment between the excited mixed-valence states mu(ab) of the dimer equals the dipole moment difference Delta of the ground and the excited bridge state of the corresponding monomer.
Collapse
Affiliation(s)
- Stephan Amthor
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | | |
Collapse
|
48
|
Amthor S, Lambert C. [2.2]Paracyclophane-Bridged Mixed-Valence Compounds: Application of a Generalized Mulliken−Hush Three-Level Model. J Phys Chem A 2005; 110:1177-89. [PMID: 16420023 DOI: 10.1021/jp0550309] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A series of [2.2]paracylophane-bridged bis-triarylamine mixed-valence (MV) radical cations were analyzed by a generalized Mulliken-Hush (GMH) three-level model which takes two transitions into account: the intervalence charge transfer (IV-CT) band which is assigned to an optically induced hole transfer (HT) from one triarylamine unit to the second one and a second band associated with a triarylamine radical cation to bridge (in particular, the [2.2]paracyclophane bridge) hole transfer. From the GMH analysis, we conclude that the [2.2]paracyclophane moiety is not the limiting factor which governs the intramolecular charge transfer. AM1-CISD calculations reveal that both through-bond as well as through-space interactions of the [2.2]paracyclophane bridge play an important role for hole transfer processes. These electronic interactions are of course smaller than direct pi-conjugation, but from the order of magnitude of the couplings of the [2.2]paracyclophane MV species, we assume that this bridge is able to mediate significant through-space and through-bond interactions and that the cyclophane bridge acts more like an unsaturated spacer rather than a saturated one. From the exponential dependence of the electronic coupling V between the two triarylamine localized states on the distance r between the two redox centers, we infer that the hole transfer occurs via a superexchange mechanism. Our analysis reveals that even significantly longer pi-conjugated bridges should still mediate significant electronic interactions because the decay constant beta of a series of pi-conjugated MV species is small.
Collapse
Affiliation(s)
- Stephan Amthor
- Institut für Organische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | | |
Collapse
|
49
|
Lambert C. Hexaarylbenzole - eine Perspektive für die torusförmige Delokalisation von Ladung und Energie. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200502105] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
50
|
Lambert C. Hexaarylbenzenes—Prospects for Toroidal Delocalization of Charge and Energy. Angew Chem Int Ed Engl 2005; 44:7337-9. [PMID: 16206312 DOI: 10.1002/anie.200502105] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Christoph Lambert
- Institut für Organische Chemie, Bayerische Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
| |
Collapse
|