1
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Shu C, Yang Z, Rajca A. From Stable Radicals to Thermally Robust High-Spin Diradicals and Triradicals. Chem Rev 2023; 123:11954-12003. [PMID: 37831948 DOI: 10.1021/acs.chemrev.3c00406] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2023]
Abstract
Stable radicals and thermally robust high-spin di- and triradicals have emerged as important organic materials due to their promising applications in diverse fields. New fundamental properties, such as SOMO/HOMO inversion of orbital energies, are explored for the design of new stable radicals, including highly luminescent ones with good photostability. A relation with the singlet-triplet energy gap in the corresponding diradicals is proposed. Thermally robust high-spin di- and triradicals, with energy gaps that are comparable to or greater than a thermal energy at room temperature, are more challenging to synthesize but more rewarding. We summarize a number of high-spin di- and triradicals, based on nitronyl nitroxides that provide a relation between the experimental pairwise exchange coupling constant J/k in the high-spin species vs experimental hyperfine coupling constants in the corresponding monoradicals. This relation allows us to identify outliers, which may correspond to radicals where J/k is not measured with sufficient accuracy. Double helical high-spin diradicals, in which spin density is delocalized over the chiral π-system, have been barely explored, with the sole example of such high-spin diradical possessing alternant π-system with Kekulé resonance form. Finally, we discuss a high-spin diradical with electrical conductivity and derivatives of triangulene diradicals.
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Affiliation(s)
- Chan Shu
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Zhimin Yang
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
| | - Andrzej Rajca
- Department of Chemistry, University of Nebraska, Lincoln, Nebraska 68588-0304, United States
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2
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Shimizu A, Morikoshi T, Sugisaki K, Shiomi D, Sato K, Takui T, Shintani R. Synthesis and Isolation of a Kekulé Hydrocarbon with a Triplet Ground State. Angew Chem Int Ed Engl 2022; 61:e202205729. [DOI: 10.1002/anie.202205729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Akihiro Shimizu
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
| | - Tetsuya Morikoshi
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
| | - Kenji Sugisaki
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
- JST PRESTO Kawaguchi, Saitama 332-0012 Japan
| | - Daisuke Shiomi
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Kazunobu Sato
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Takeji Takui
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Ryo Shintani
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
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3
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Wu F, Ma J, Lombardi F, Fu Y, Liu F, Huang Z, Liu R, Komber H, Alexandropoulos DI, Dmitrieva E, Lohr TG, Israel N, Popov AA, Liu J, Bogani L, Feng X. Benzo-Extended Cyclohepta[def]fluorene Derivatives with Very Low-Lying Triplet States. Angew Chem Int Ed Engl 2022; 61:e202202170. [PMID: 35290699 PMCID: PMC9324097 DOI: 10.1002/anie.202202170] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Indexed: 12/24/2022]
Abstract
Open-shell non-alternant polycyclic hydrocarbons (PHs) are attracting increasing attention due to their promising applications in organic spintronics and quantum computing. Herein we report the synthesis of three cyclohepta[def]fluorene-based diradicaloids (1-3), by fusion of benzo rings on its periphery for the thermodynamic stabilization, as evidenced by multiple characterization techniques. Remarkably, all of them display a very narrow optical energy gap (Eg opt =0.52-0.69 eV) and persistent stability under ambient conditions (t1/2 =11.7-33.3 h). More importantly, this new type of diradicaloids possess a low-lying triplet state with an extremely small singlet-triplet energy gap, as low as 0.002 kcal mol-1 , with a clear dependence on the molecular size. This family of compounds thus offers a new route to create non-alternant open-shell PHs with high-spin ground states, and opens up novel possibilities and insights into understanding the structure-property relationships.
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Affiliation(s)
- Fupeng Wu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
| | - Ji Ma
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
| | | | - Yubin Fu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials Research01069DresdenGermany
| | - Zhijie Huang
- Department of MaterialsUniversity of OxfordOxfordOX1 3PHUK
| | - Renxiang Liu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
| | - Hartmut Komber
- Leibniz-Institut für Polymerforschung Dresden e. V.Hohe Straße 601069DresdenGermany
| | | | - Evgenia Dmitrieva
- Leibniz Institute for Solid State and Materials Research01069DresdenGermany
| | - Thorsten G. Lohr
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
| | - Noel Israel
- Leibniz Institute for Solid State and Materials Research01069DresdenGermany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials Research01069DresdenGermany
| | - Junzhi Liu
- Department of Chemistry and State Key Laboratory of Synthetic ChemistryThe University of Hong KongPokfulam RoadHong KongChina
| | - Lapo Bogani
- Department of MaterialsUniversity of OxfordOxfordOX1 3PHUK
| | - Xinliang Feng
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food ChemistryTechnische Universität DresdenMommsenstrasse 401062DresdenGermany
- Max Planck Institute of Microstructure PhysicsWeinberg 206120HalleGermany
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4
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Shimizu A, Morikoshi T, Sugisaki K, Shiomi D, Sato K, Takui T, Shintani R. Synthesis and Isolation of a Kekulé Hydrocarbon with a Triplet Ground State. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Akihiro Shimizu
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
| | - Tetsuya Morikoshi
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
| | - Kenji Sugisaki
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
- JST PRESTO Kawaguchi, Saitama 332-0012 Japan
| | - Daisuke Shiomi
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Kazunobu Sato
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Takeji Takui
- Department of Chemistry and Molecular Materials Science Graduate School of Science Osaka City University Sumiyoshi-ku, Osaka 558-8585 Japan
| | - Ryo Shintani
- Division of Chemistry Department of Materials Engineering Science Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
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5
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Wu F, Ma J, Lombardi F, Fu Y, Liu F, Huang Z, Liu R, Komber H, Alexandropoulos DI, Dmitrieva E, Lohr TG, Israel N, Popov AA, Liu J, Bogani L, Feng X. Benzo‐Extended Cyclohepta[
def
]fluorene Derivatives with Very Low‐Lying Triplet States. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Fupeng Wu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
| | - Ji Ma
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
| | | | - Yubin Fu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
| | - Fupin Liu
- Leibniz Institute for Solid State and Materials Research 01069 Dresden Germany
| | - Zhijie Huang
- Department of Materials University of Oxford Oxford OX1 3PH UK
| | - Renxiang Liu
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
| | - Hartmut Komber
- Leibniz-Institut für Polymerforschung Dresden e. V. Hohe Straße 6 01069 Dresden Germany
| | | | - Evgenia Dmitrieva
- Leibniz Institute for Solid State and Materials Research 01069 Dresden Germany
| | - Thorsten G. Lohr
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
| | - Noel Israel
- Leibniz Institute for Solid State and Materials Research 01069 Dresden Germany
| | - Alexey A. Popov
- Leibniz Institute for Solid State and Materials Research 01069 Dresden Germany
| | - Junzhi Liu
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry The University of Hong Kong Pokfulam Road Hong Kong China
| | - Lapo Bogani
- Department of Materials University of Oxford Oxford OX1 3PH UK
| | - Xinliang Feng
- Center for Advancing Electronics Dresden (cfaed) & Faculty of Chemistry and Food Chemistry Technische Universität Dresden Mommsenstrasse 4 01062 Dresden Germany
- Max Planck Institute of Microstructure Physics Weinberg 2 06120 Halle Germany
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6
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Hirao Y, Daifuku Y, Ihara K, Kubo T. Spin–Spin Interactions in One‐Dimensional Assemblies of a Cumulene‐Based Singlet Biradical. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yasukazu Hirao
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Yoko Daifuku
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Keiji Ihara
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Takashi Kubo
- Department of Chemistry Graduate School of Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
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7
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Hirao Y, Daifuku Y, Ihara K, Kubo T. Spin-Spin Interactions in One-Dimensional Assemblies of a Cumulene-Based Singlet Biradical. Angew Chem Int Ed Engl 2021; 60:21319-21326. [PMID: 34101316 DOI: 10.1002/anie.202105740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Indexed: 11/09/2022]
Abstract
The synthesis of phenalenyl-endcapped [5]cumulene as a cumulene-based singlet biradical and the spin correlation changes of one-dimensional aggregates are described. The high propensity for self-aggregation of phenalenyl rings and the introduction of bulky substituents into the appropriate positions led to the formation of a one-dimensional chain assembly. Single-crystal X-ray structural analysis indicated that the bond length alternation of the cumulene chain increased with decreasing temperature, along with improved overlapping of the phenalenyl rings. Variable-temperature Raman spectroscopy and magnetic susceptibility measurements revealed that a localized spin pair within the molecule decouples at low temperatures, and a continuum spin system involving intra- and intermolecular spin-spin interactions emerges in the one-dimensional chain.
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Affiliation(s)
- Yasukazu Hirao
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yoko Daifuku
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Keiji Ihara
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
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9
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Matsunaga Y, Takeda K. Ground-state molecular and electronic structures of group-IV nanoribbons, nanorings and nanotubes. Phys Chem Chem Phys 2018; 20:24353-24368. [PMID: 30215061 DOI: 10.1039/c8cp04566f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Based on ab initio molecular orbital (MO) theory and first-principles band calculations, we systematically study the ground-state molecular and electronic structures of group-IV nanoribbons (NRBs), nanorings (NRGs) and nanotubes (NTBs) by substituting the honeycomb skeletal atoms with C, Si or Ge atoms. We then explore the energetics in the ground-state singlet-triplet (ST) crossover, particularly focusing on the configuration hybridization by electron correlation.
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Affiliation(s)
- YouKey Matsunaga
- Faculty of Advanced Science and Engineering, Shijyuku, Tokyo, Japan
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10
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Vazdar M, Eckert-Maksić M, Lischka H. The Antiferromagnetic Spin Coupling in Non-Kekulé Acenes-Impressive Polyradical Character Revealed by High-Level Multireference Methods. Chemphyschem 2016; 17:2013-21. [PMID: 26990145 DOI: 10.1002/cphc.201600103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Indexed: 11/07/2022]
Abstract
Complete active space (CASSCF) and multireference (MR-CISD(Q) and MR-AQCC) calculations were performed for non-Kekulé analogues of acenes, dimethylenepolycyclobutadienes, with lengths of up to eight cyclobutadiene (CBD) units. Multireference calculations predict that the most stable energy state of the system is either triplet (if there is an odd number of CBD units) or singlet (if there is an even number of CBD units) due to antiferromagnetic spin coupling, which thus violates Hund's rule in larger molecules. We also show an impressive polyradical character in the system that increases with the size of the molecule, as witnessed by more than eleven unpaired electrons in the singlet state of the molecule with eight CBD units. Together with the small energy gap between singlet and higher multiplicity energy states even above the triplet state, this demonstrates the exceptional polyradical properties of these π-conjugated oligomeric chains.
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Affiliation(s)
- Mario Vazdar
- Division of Organic Chemistry and Biochemistry, Rudjer Bosković Institute, P.O.B. 180, HR-10002, Zagreb, Croatia.
| | - Mirjana Eckert-Maksić
- Division of Organic Chemistry and Biochemistry, Rudjer Bosković Institute, P.O.B. 180, HR-10002, Zagreb, Croatia.
| | - Hans Lischka
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, 79409-1061, USA. .,Institute for Theoretical Chemistry, University of Vienna, Währingerstrasse 17, A-1090, Vienna, Austria. .,School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin, 300072, P.R.China.
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11
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Nikolić JD, Wouters S, Romanova J, Shimizu A, Champagne B, Junkers T, Vanderzande D, Van Neck D, Waroquier M, Van Speybroeck V, Catak S. PPV Polymerization through the Gilch Route: Diradical Character of Monomers. Chemistry 2015; 21:19176-85. [PMID: 26568272 DOI: 10.1002/chem.201501900] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Indexed: 11/08/2022]
Abstract
Despite various studies on the polymerization of poly(p-phenylene vinylene) (PPV) through different precursor routes, detailed mechanistic knowledge on the individual reaction steps and intermediates is still incomplete. The present study aims to gain more insight into the radical polymerization of PPV through the Gilch route. The initial steps of the polymerization involve the formation of a p-quinodimethane intermediate, which spontaneously self-initiates through a dimerization process leading to the formation of diradical species; chain propagation ensues on both sides of the diradical or chain termination occurs by the formation of side products, such as [2.2]paracyclophanes. Furthermore, different p-quinodimethane systems were assessed with respect to the size of their aromatic core as well as the presence of heteroatoms in/on the conjugated system. The nature of the aromatic core and the specific substituents alter the electronic structure of the p-quinodimethane monomers, affecting the mechanism of polymerization. The diradical character of the monomers has been investigated with several advanced methodologies, such as spin-projected UHF, CASSCF, CASPT2, and DMRG calculations. It was shown that larger aromatic cores led to a higher diradical character in the monomers, which in turn is proposed to cause rapid initiation.
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Affiliation(s)
- Jelena D Nikolić
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium).,Faculty of Science, University of Kragujevac, 12 Radoja Domanovića, 34000 Kragujevac (Serbia)
| | - Sebastian Wouters
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium).,Current address: Department of Chemistry, Princeton University, Frick Chemistry Laboratory, Princeton, New Jersey 08544 (USA)
| | - Julia Romanova
- Laboratoire de Chimie Théorique, University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium).,Current address: Advanced Technology Institute, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH. (UK)
| | - Akihiro Shimizu
- Laboratoire de Chimie Théorique, University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium).,Current address: Department of Synthetic and Biological Chemistry, Kyoto University, Kyoto, (Japan)
| | - Benoît Champagne
- Laboratoire de Chimie Théorique, University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium).
| | - Tanja Junkers
- Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt (Belgium).,IMEC, IMOMEC Ass. Lab., Universitaire Campus, Wetenschapspark 1, 3590 Diepenbeek (Belgium)
| | - Dirk Vanderzande
- Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt (Belgium).,IMEC, IMOMEC Ass. Lab., Universitaire Campus, Wetenschapspark 1, 3590 Diepenbeek (Belgium)
| | - Dimitri Van Neck
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium)
| | - Michel Waroquier
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium)
| | - Veronique Van Speybroeck
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium)
| | - Saron Catak
- Center for Molecular Modeling, Ghent University, Technologie Park 903, Zwijnaarde, 9052 (Belgium). .,Department of Chemistry, Bogazici University, Bebek, Istanbul, 34342 (Turkey).
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Das S, Wu J. Toward Singlet–Triplet Bistable Nonalternant Kekulé Hydrocarbons: Azulene-to-Naphthalene Rearrangement. Org Lett 2015; 17:5854-7. [DOI: 10.1021/acs.orglett.5b03028] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Soumyajit Das
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Jishan Wu
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
- Institute of Materials
Research and Engineering, A*STAR, 2 Fusionopolis Way, Innovis, #08-03, Singapore 117602, Singapore
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13
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Qualizza BA, Ciszek JW. Experimental survey of the kinetics of acene Diels-Alder reactions. J PHYS ORG CHEM 2015. [DOI: 10.1002/poc.3463] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Brittni A. Qualizza
- Department of Chemistry and Biochemistry; Loyola University Chicago; 1032 W. Sheridan Rd Chicago IL 60660 USA
| | - Jacob W. Ciszek
- Department of Chemistry and Biochemistry; Loyola University Chicago; 1032 W. Sheridan Rd Chicago IL 60660 USA
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14
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Electronic structure study of the biradical pleiadene-like molecules. MONATSHEFTE FUR CHEMIE 2013. [DOI: 10.1007/s00706-013-1114-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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15
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Affiliation(s)
- Manabu Abe
- Department of Chemistry, Graduate School of Science, Hiroshima University (HIRODAI), 1-3-1 Kagamiyama, Higashi-Hiroshima,
Hiroshima 739-8526, Japan
- Institute for Molecular Science (IMS), Okazaki, Aichi 444-8787,
Japan
- JST-CREST, 5
Sanbancho,
Chiyodaku, Tokyo 102-0075, Japan
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16
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Radenković S, Marković S, Milenković V. Electronic structure study of the triplet azulene-like molecules. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.07.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Kanawati B, Genest A, Schmitt-Kopplin P, Lenoir D. Bis-dibenzo[a.i]fluorenylidene, does it exist as stable 1,2-diradical? J Mol Model 2012; 18:5089-95. [DOI: 10.1007/s00894-012-1502-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 06/08/2012] [Indexed: 11/24/2022]
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18
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Snyder GJ. Rational design of high-spin biradicaloids in the isobenzofulvene and isobenzoheptafulvene series. J Phys Chem A 2012; 116:5272-91. [PMID: 22548674 DOI: 10.1021/jp304015k] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The relative energies of singlet biradicaloid and of triplet and singlet biradical electronic states for a series of benzannelated isobenzofulvenes and isobenzoheptafulvenes were calculated at the (u-)B3LYP/6-31G(d), full π-space CASSCF-CASPT2 (≤14 π-e(-)s), and full π-space RASSCF-RASPT2 (≤24 π-e(-)s) levels of theory. Both absolute and relative CASPT2 energies were reproduced quite well by the RASPT2 approach, which can be extended to much larger active spaces. RASPT2 (and DFT) calculations find that increasing benzannelation leads to triplet ground states in both hydrocarbon series, in violation of the classical principle of maximum bonding. This confirmed the expectations that the combined effects of resonance energy and aromaticity could compensate for the extra formal π-bond of the biradicaloid singlet, and that the strong exchange coupling inherent to the embedded trimethylenemethane (TMM) would manifest itself in the biradicaloids. The relative energy of the biradicaloid singlet rises rapidly upon benzannelation, as π-bonding between the high-energy delocalized GVB orbitals decreases. The underlying π-orbital topology is revealed when this weak π-bonding is artificially eliminated by a 1:1 mixing of the nondegenerate HOMO and LUMO to produce an overcorrelated valence bond (OCVB) orbital pair. For members of both biradicaloid series, the OCVB pairs are nondisjoint, revealing a limiting triplet preference with increasing benzannelation. Within the two-electron, two-orbital approximation, the effects of π-bonding in the singlet biradicaloids and orbital localization away from the acene π-system in the triplet biradicals can be analyzed as perturbations of the singlet OCVB biradicals. The application of a VB-based spin coupling scheme is discussed, in which the unpaired electrons of these species can be considered both ferromagnetically and antiferromagnetically coupled, with the strength of the latter strongly dependent on the acene subunit.
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Affiliation(s)
- Gary J Snyder
- Department of Chemistry, Amherst College, Amherst, Massachusetts 01002, USA.
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21
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Marković S, Radenković S, Marković Z, Gutman I. DFT study on singlet diradical character of zethrenes. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2011. [DOI: 10.1134/s0036024411130127] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Saranya G, Kolandaivel P, Senthilkumar K. Optical absorption and emission properties of fluoranthene, benzo[k]fluoranthene, and their derivatives. A DFT study. J Phys Chem A 2011; 115:14647-56. [PMID: 22077554 DOI: 10.1021/jp208617s] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fluoranthene and benzo[k]fluoranthene-based oligoarenes are good candidates for organic light-emitting diodes (OLEDs). In this work, the electronic structure and optical properties of fluoranthene, benzo[k]fluoranthene, and their derivatives have been studied using quantum chemical methods. The ground-state structures were optimized using the density functional theory (DFT) methods. The lowest singlet excited state was optimized using time-dependent density functional theory (TD-B3LYP) and configuration interaction singles (CIS) methods. On the basis of ground- and excited-state geometries, the absorption and emission spectra have been calculated using the TD-DFT method with a variety of exchange-correlation functionals. All the calculations were carried out in chloroform medium. The results show that the absorption and emission spectra calculated using the B3LYP functional is in good agreement with the available experimental results. Unlikely, the meta hybrid functionals such as M06HF and M062X underestimate the absorption and emission spectra of all the studied molecules. The calculated absorption and emission wavelength are more or less basis set independent. It has been observed that the substitution of an aromatic ring significantly alters the absorption and emission spectra.
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Affiliation(s)
- G Saranya
- Department of Physics, Bharathiar University, Coimbatore, India-641 046
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Shimizu A, Nakano M, Hirao Y, Kubo T. Experimental consideration of covalent-bonding interactions in stacks of singlet biradicals having Kekulé structures. J PHYS ORG CHEM 2011. [DOI: 10.1002/poc.1873] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Akihiro Shimizu
- Department of Chemistry, Graduate School of Science; Osaka University; Toyonaka Osaka 560-0043 Japan
| | - Masayoshi Nakano
- Department of Materials Engineering Science, Graduate School of Engineering Science; Osaka University; Toyonaka Osaka 560-8531 Japan
| | - Yasukazu Hirao
- Department of Chemistry, Graduate School of Science; Osaka University; Toyonaka Osaka 560-0043 Japan
| | - Takashi Kubo
- Department of Chemistry, Graduate School of Science; Osaka University; Toyonaka Osaka 560-0043 Japan
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Carbon–nitrogen nanorings and nanoribbons: a theoretical approach for altering the ground states of cyclacenes and polyacenes. MONATSHEFTE FUR CHEMIE 2010. [DOI: 10.1007/s00706-010-0398-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Marković S, Đurđević J, Jeremić S, Gutman I. Triplet fluoranthenes: Aromaticity versus unpaired electrons. J Mol Model 2010; 17:805-10. [DOI: 10.1007/s00894-010-0778-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 06/07/2010] [Indexed: 12/01/2022]
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Hajgató B, Szieberth D, Geerlings P, De Proft F, Deleuze MS. A benchmark theoretical study of the electronic ground state and of the singlet-triplet split of benzene and linear acenes. J Chem Phys 2009; 131:224321. [DOI: 10.1063/1.3270190] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Quast H, Nüdling W, Klemm G, Kirschfeld A, Neuhaus P, Sander W, Hrovat DA, Borden WT. A Perimidine-Derived Non-Kekulé Triplet Diradical. J Org Chem 2008; 73:4956-61. [DOI: 10.1021/jo800589y] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Helmut Quast
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Wolfgang Nüdling
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Gerhard Klemm
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Andreas Kirschfeld
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Patrik Neuhaus
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Wolfram Sander
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - David A. Hrovat
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
| | - Weston Thatcher Borden
- Institut für Organische Chemie der Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany, Lehrstuhl für Organische Chemie II der Ruhr-Universität Bochum, D-44780 Bochum, Germany, and Department of Chemistry, University of North Texas, P.O. Box 305070, Denton, Texas 76203-5070
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Kubo T, Goto Y, Uruichi M, Yakushi K, Nakano M, Fuyuhiro A, Morita Y, Nakasuji K. Synthesis and characterization of acetylene-linked bisphenalenyl and metallic-like behavior in its charge-transfer complex. Chem Asian J 2008; 2:1370-9. [PMID: 17828719 DOI: 10.1002/asia.200700147] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We prepared and isolated a phenalenyl-based neutral hydrocarbon (1 b) with a biradical index of 14%, as well as its charge-transfer (CT) complex 1 b-F(4)-TCNQ. The crystal structure and the small HOMO-LUMO gap assessed by electrochemical and optical methods support the singlet-biradical contribution to the ground state of the neutral 1 b. This biradical character suggests that 1 b has the electronic structure of phenalenyl radicals coupled weakly through an acetylene linker, that is, some independence of the two phenalenyl moieties. The monocationic species 1 b*+ was obtained by reaction with the organic electron acceptor F4-TCNQ. The cationic species has a small disproportionation energy deltaE for the reaction 2 x 1 b*+ <==> 1 b + 1 b2+, which presumably originates from the independence of the phenalenyl moieties. The small deltaE led to a small on-site Coulombic repulsion U(eff) = 0.61 eV in the CT complex. Moreover, a very effective orbital overlap of the phenalenyl rings between molecules afforded a relatively large transfer integral t = 0.09 eV. The small U(eff)/4t ratio (= 1.7) resulted in a metallic-like conductive behavior at around room temperature. Below 280 K, the CT complex showed a transition into a semiconductive state as a result of bond formation between phenalenyl and F4-TCNQ carbon atoms.
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Affiliation(s)
- Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan.
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Kubo T, Shimizu A, Uruichi M, Yakushi K, Nakano M, Shiomi D, Sato K, Takui T, Morita Y, Nakasuji K. Singlet Biradical Character of Phenalenyl-Based Kekulé Hydrocarbon with Naphthoquinoid Structure. Org Lett 2006; 9:81-4. [PMID: 17192090 DOI: 10.1021/ol062604z] [Citation(s) in RCA: 137] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] A new Kekulé polycyclic hydrocarbon with a singlet biradical index of 50% was synthesized. The singlet biradical character was assessed with UV and 1H-NMR spectroscopy, cyclic voltammetry, SQUID magnetic susceptibility measurement, and quantum chemical calculations.
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Affiliation(s)
- Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
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Nakano M, Kishi R, Ohta S, Takebe A, Takahashi H, Furukawa SI, Kubo T, Morita Y, Nakasuji K, Yamaguchi K, Kamada K, Ohta K, Champagne B, Botek E. Origin of the enhancement of the second hyperpolarizability of singlet diradical systems with intermediate diradical character. J Chem Phys 2006; 125:074113. [PMID: 16942328 DOI: 10.1063/1.2213974] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The origin of the diradical character dependence of the second hyperpolarizability (gamma) of neutral singlet diradical systems is clarified based on the perturbation formula of gamma using the simplest diradical molecular model with different diradical characters, i.e., H2 under bond dissociation. The enhancement of gamma in the intermediate diradical character region turns out to originate from the increasing magnitude of the transition moment between the first and second excited states and the decrease of that between the ground and first excited states, respectively, with the increase in diradical character. This feature confirms that open-shell singlet conjugated molecules with intermediate diradical characters constitute a new class of third-order nonlinear optical systems, whose gamma values can be controlled by the diradical character in addition to the conjugation length.
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Affiliation(s)
- Masayoshi Nakano
- of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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Nakano M, Kubo T, Kamada K, Ohta K, Kishi R, Ohta S, Nakagawa N, Takahashi H, Furukawa SI, Morita Y, Nakasuji K, Yamaguchi K. Second hyperpolarizabilities of polycyclic aromatic hydrocarbons involving phenalenyl radical units. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2005.10.109] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Kubo T, Sakamoto M, Nakasuji K. Biradicaloid character of phenalenyl-based aromatic compounds with a small HOMO–LUMO gap. Polyhedron 2005. [DOI: 10.1016/j.poly.2005.03.072] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Kubo T, Shimizu A, Sakamoto M, Uruichi M, Yakushi K, Nakano M, Shiomi D, Sato K, Takui T, Morita Y, Nakasuji K. Synthesis, Intermolecular Interaction, and Semiconductive Behavior of a Delocalized Singlet Biradical Hydrocarbon. Angew Chem Int Ed Engl 2005; 44:6564-8. [PMID: 16158453 DOI: 10.1002/anie.200502303] [Citation(s) in RCA: 252] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan.
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Kubo T, Shimizu A, Sakamoto M, Uruichi M, Yakushi K, Nakano M, Shiomi D, Sato K, Takui T, Morita Y, Nakasuji K. Synthesis, Intermolecular Interaction, and Semiconductive Behavior of a Delocalized Singlet Biradical Hydrocarbon. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200502303] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Kikuchi A, Ito H, Abe J. A New Family of π-Conjugated Delocalized Biradicals: Electronic Structures of 1,4-Bis(2,5-diphenylimidazol-4-ylidene)cyclohexa-2,5-diene. J Phys Chem B 2005; 109:19448-53. [PMID: 16853513 DOI: 10.1021/jp052207q] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new family of pi-conjugated delocalized biradical compound is developed. The solution of 1,4-bis(2,5-diphenylimidazol-4-ylidene)cyclohexa-2,5-diene shows the ESR signal consisting of a moderately broad unresolved line, Delta H(pp) approximately 1 mT, at room temperature. The presence of the thermal equilibrium between a triplet biradical state and a singlet state is confirmed by the ESR measurements, and the spin concentration is determined as 7.90 x 10(21) spin/mol at 300 K. The spin concentration can also be controlled by modifying the molecular planarity. Moreover, the unrestricted DFT/B3LYP calculations suggest the biradical character of the singlet ground state, and the modulation of the energy gap between the singlet state and the triplet state is investigated from the theoretical point of view. Controlling the equilibrium between a diamagnetic state and a paramagnetic state will provide significant progress in the field of biradical chemistry, and the materials with the biradical character in a ground state will lead to a novel development of molecular-based organic magnets.
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Affiliation(s)
- Azusa Kikuchi
- Department of Chemistry, and The 21st Century COE Program, Aoyama Gakuin University, 5-10-1 Fuchinobe, Sagamihara, Kanagawa 229-8558, Japan
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Nakano M, Kishi R, Nitta T, Kubo T, Nakasuji K, Kamada K, Ohta K, Champagne B, Botek E, Yamaguchi K. Second Hyperpolarizability (γ) of Singlet Diradical System: Dependence of γ on the Diradical Character. J Phys Chem A 2005; 109:885-91. [PMID: 16838960 DOI: 10.1021/jp046322x] [Citation(s) in RCA: 271] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dependence of the second hyperpolarizability (gamma) on the diradical character (y) for singlet diradical systems is investigated using a model compound, the p-quinodimethane (PQM) molecule with different both-end carbon-carbon (C-C) bond lengths, by several ab initio molecular orbital and density functional theory methods. The diradical character based on UHF calculations indicates that at equilibrium geometry PQM is in a singlet ground state and primarily exhibits a quinoid structure, whereas the diradical character increases when increasing both-end C-C bond lengths. At the highest level of approximation, that is, using the UCCSD(T) method with the 6-31G+diffuse p (zeta = 0.0523) basis set, the longitudinal static gamma of PQM presents a maximum value for intermediate diradical character (y approximately 0.5) while the gamma values are larger for intermediate and large diradical character (y approximately 0.5-0.7) than for small diradical character (y < 0.2). This feature suggests that the gamma values of singlet diradical systems in the intermediate and somewhat strong correlation regimes are significantly enhanced as compared to those in the weak correlation regime. These results are substantiated by a complementary study of the variation in gamma upon twisted ethylene.
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Affiliation(s)
- Masayoshi Nakano
- Division of Chemical Engineering, Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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Kubo T, Sakamoto M, Akabane M, Fujiwara Y, Yamamoto K, Akita M, Inoue K, Takui T, Nakasuji K. Four-Stage Amphoteric Redox Properties and Biradicaloid Character of Tetra-tert-butyldicyclopenta[b;d]thieno[1,2,3-cd;5,6,7-c?d?]diphenalene. Angew Chem Int Ed Engl 2004. [DOI: 10.1002/ange.200460565] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kubo T, Sakamoto M, Akabane M, Fujiwara Y, Yamamoto K, Akita M, Inoue K, Takui T, Nakasuji K. Four-Stage Amphoteric Redox Properties and Biradicaloid Character of Tetra-tert-butyldicyclopenta[b;d]thieno[1,2,3-cd;5,6,7-c?d?]diphenalene. Angew Chem Int Ed Engl 2004; 43:6474-9. [PMID: 15578787 DOI: 10.1002/anie.200460565] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Takashi Kubo
- Department of Chemistry, Graduate School of Science, Osaka University, Machikaneyama 1-1, Toyonaka, Osaka 560-0043, Japan.
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Abe M, Ishihara C, Nojima M. DFT prediction of ground-state spin multiplicity of cyclobutane-1,3-diyls: notable effects of two sets of through-bond interactions. J Org Chem 2003; 68:1618-21. [PMID: 12585920 DOI: 10.1021/jo026345c] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
DFT calculations (UB3LYP/6-31+G**) have been performed to predict the substituent effect on the ground-state spin-multiplicity and the singlet-triplet energy gap in cyclobutane-1,3-diyls, CB-DR. The ground state is calculated to be largely dependent on the substituents (X, Y) at the C2 and C4 positions. The substituent effects can be reasonably explained by the two sets of through-bond (TB) interactions which result from the coupling between the symmetric nonbonding molecular orbital (Psi(S)) and the C-X (Y) sigma and sigma* orbitals.
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Affiliation(s)
- Manabu Abe
- Department of Materials Chemistry & Frontier Research Center (HANDAI FRC), Graduate School of Engineering, Osaka University (HANDAI), Suita 565-0871, Osaka, Japan.
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