1992 Fiscal Year Annual Research Report

分子磁性発現とその機構

Research Project

Project/Area Number	04242103
Research Institution	The University of Tokyo
Principal Investigator	木下實東京大学, 物性研究所, 教授 (40011530)
Co-Investigator(Kenkyū-buntansha)	阿波賀邦夫東京大学, 教養学部, 助教授 (10202772) 工位武治大阪市立大学, 理学部, 教授 (10117955) 榎敏明東京工業大学, 理学部, 教授 (10113424) 志田忠正京都大学, 理学部, 教授 (60025484)
Keywords	分子磁性 / 有機高スピン分子 / 有機強磁性体 / 磁気相互作用 / 伝導性と磁性 / 反強磁性 / 伝導性有機物質 / 磁性
Research Abstract	高スピン分子の関係の研究では,今回新たに2次元的に広がったπ電子軌道をもつ分子が合成され,その電子常磁性共鳴(EPR)スペクトルの解析が行われた。スペクトル強度の温度依存性から基底状態は13重項であることが示され,ゼロ磁場分裂定数はD=+0.01909cm^<-1>,E=0.00193cm^<-1>と決定された。これは現在報告されている分子としては,最高のスピン多重度をもつものである。一方,基底状態が5重項のカルベン分子の陽イオンでは,基底状態が4重項になるが,EPRスペクトルの解析から僅かではあるが構造の異なる2種類のイオンが生成していることがわかった。また,7重項の分子の陰イオンのEPRスペクトル観測にも成功しているが,実験上の因難もあり検証に努める必要がある。分子性錯体の研究では,(BEDT-TTF)_6Cu_2Br_8で反強磁性体が得られた。この物質は、常圧で半導体特性をもつが6kbar以上の高圧下で金属伝導を示す伝導性の高い物質である。そのスピン磁化率はキュリー・ワイス則になるが,大きな反強磁性的ワイス定数θ=-140Kを与え,さらに低温では長距離秩序が形成しT_n=7.5Kの反強磁性状態になる。2次元のハイゼンベルグ模型の解析では,Cu^<2+>スピン間にJ=-17Kという大きな交換相互作用が働いていることになり,BEDT-TTF上のπ電子を介してのπ-d相互作用によると考えられる。 T_C=0.6Kで強磁性体になるp-NPNNについては,T_C以下の温度でミュオンスピン回転による自発磁化の観測とその温度変化が調べられ,各磁区のモーメントは,b磁区方向に揃っていることがわかった。ニトロニルニトロキシド系のラジカルでは,光電子スペクトルの測定から強磁性相互作用の機構に重要な示唆が得られ,またその陽イオンラジカルの場合には,対イオンを変えると磁性が大きく変化することが示された。新たに,ベルダジル系のラジカルについても置換基による系統的な磁気相互作用の変化が見いだされた。

Research Products

(38 results)

All Other

All Publications (38 results)

[Publications] M.Kinoshita: "Finding of bulk ferromagnetism in stable organic radical crystal." Materials Research Society Symposium Proceedings. 247. 429-432 (1992)
[Publications] Y.Nakazawa: "Low temperature magnetic properties of ferromagnetic organic radical,p-NPNN." Physical Review B. 46. 8906-8914 (1992)
[Publications] M.Takahashi: "Mean-field theory of quasi one-dimensional Heisenberg magnet γ-phase p-NPNN." Journal of the Physical Society of Japan. 61. 3745-3751 (1992)
[Publications] T.Sugano: "Ferromagnetic intermolecular interaction in an organic redical,3-quinolyl nitronyl nitroxide(3-QNNN)." Chemical Physics Letters. 200. 235-240 (1992)
[Publications] D.Shiomi: "Magnetic properties of an organic biradical,m-BNN:m-Phenylene bis(α-nitronyl nitroxide)." Journal of the Physical Society of Japan. 62. 289-300
[Publications] M.Kinoshita: "Bulk ferromagnetism of the crystal of the organic radical,p-NPNN." Synthetic Metals. (1993)
[Publications] D.Shiomi: "Novel magnetic interactions in organic polyradical crystals based on nitronyl nitroxide." Synthetic Metals. (1993)
[Publications] K.Nozawa: "Magnetic properties and crystal structures of some nitronyl nitroxide derivatives." Synthetic Metals. (1993)
[Publications] D.Shiomi: "Magnetic energy gap in the crystal of an organic bi-radical,m-BNN:m-Phenylene bis(α-nitronyl nitroxide)." Molecular Crystals and Liquid Crystals. (1993)
[Publications] M.Tamura: "Magnetic properties of phenyl nitronyl nitroxides." Molecular Crystals and Liquid Crystals. (1993)
[Publications] M.Kinoshita: "Ferromagnetism in organic radical crystal." Molecular Crystals and Liquid Crystals. (1993)
[Publications] L.P.Le: "Searching spontaneous magnetic order by μSR in an organic ferromagnet---β-phase p-NPNN." Chemical Physics Letters. (1993)
[Publications] R.Kato: "Proparation and physical properties of an alloyed (DMe-DCNQI)_2Cu with fully deuterated DMe-DCNQI(DMe-DCNQI=2,5-dimethyl-N,N'-dicyanoquinonediimine)." Solid State Communications. (1993)
[Publications] M.Matsushita: "Novel organic ions of high-spin states.II:Determination of the spin multiplicity of the ground state and 1H-ENDOR study of the monoanion of m-phenylenbis(phenylmethylene)" Journal of the American Chemical Society. 114. 7470-7475 (1992)
[Publications] M.Matsushita: "Novel organic ions of high-spin states.III:Determination of the spin multiplicity of the ground state and 1H-ENDOR study of the monocation of m-phenylenebis(...)." Bulletin of the Chemical Society of Japan. (1993)
[Publications] T.Kondo: "Trasnport and magnetic properties of incommensurate layer compounds (RES)_XVS_2(RE=Rare Earth)." Solid State Communications. 84. 999-1003 (1992)
[Publications] T.Ishii: "Electronic properties of gold trichloride-graphite intercalation compound(AuCl_3-GICs)." Solid State Communications. 84. 1055-1058 (1992)
[Publications] K.Suzuki: "Phase transitions and magnetic properties of an organic conductor (BEDT-TTF)_6Cu_2Br_6 with mixed valence Cu ions." Synthetic Metals. (1993)
[Publications] K.Suzuki: "Conduction mechanism and two-dimensional magnetism in incommensurate layered compounds (RES)xMS2(RE=Rare Earth metal,M=Ta,V)." Synthetic Metals. (1993)
[Publications] T.Enoki: "Solid state properties of charge transfer complexes of TTF derivatives with 3d-transition metal halides." Molecular Crystals and Liquid Crystals. (1993)
[Publications] A.Nakayama: "Magnetic properties of activated carbon fibers." Synthetic Metals. (1993)
[Publications] Y.Miura: "Molecular design,synthesis and magnetic characterization of poly(phenylacetylene) with π-toporegurated pendant nitronyl nitroxide radicals as models for..." Journal of the Polymer Society. 30. 956-966 (1992)
[Publications] Y.Teki: "Topology and spin alignment in a novel organic high-spin molecule,biphenyl-3,4'-bis(phenylmethylene),as studied by ESR and a generalized UHF Hubbard calculation." Journal of the American Chemical Society. (1993)
[Publications] Y.Teki: "Topology and spin alignment in organic high-spin molecules." Bulletin of Magnetic Resonance. 14. (1992)
[Publications] K.Furukawa: "Molecular design,synthesis,and electron spin resonance detection of a ground-state tridecet(S=6) hydrocarbon as a model for 2D organic ferro- and superpara-magnets." Bulletin of Magnetic Resonance. 15. (1993)
[Publications] T.Takui: "Organic high-spin state ENDOR/TRIPLE spectroscopy:Spin and molecular structural studies of models for organic ferro- and superpara-magnets." Bulletin of Magnetic Resonance. 15. (1993)
[Publications] Y.Teki: "Role of the spin correlation and weakly interacting model for the spin alignment in organic high-spin molecules." Molecular Crystals and Liquid Crystals. (1993)
[Publications] K.Sato: "Spin polarization effect in organic high-spin molecules as studied by single crystal ESR and 1H-ENDOR spectroscopies." Molecular Crystals and Liquid Crystals. (1993)
[Publications] K.Furukawa: "Molecular design,synthesis,and electron spin resonance detection of a ground-state tridecet(S=6) hydrocarbon as a model for 2D organic ferro- and superpara-magnets." Molecular Crystals and Liquid Crystals. (1993)
[Publications] Y.Teki: "Magnetic behavior of (N-arylthio)-2,4,6-triphenylanilino radical crystals." Molecular Crystals and Liquid Crystals. (1993)
[Publications] Y.Miura: "Synthesis of nitroxide polyradicals by catalytic polycondensation of 3,5-diethylbenzenes carrying nitroxide radicals with diiodobenzenes and their magnetic..." Molecular Crystals and Liquid Crystals. (1993)
[Publications] Y.Teki: "Novel organic ions of high-spin states." Molecular Crystals and Liquid Crystals. (1993)
[Publications] T.Takui: "Unusually large negative spin polarization of hetero-spin composite high-spin carbenes as models for purely organic ferrimagnets:Topological through-bond..." Molecular Crystals and Liquid Crystals. (1993)
[Publications] K.Awaga: "Ferromagnetic and antiferromagnetic intermolecular interactions in the two-dimensional triangular lattice of an α-nitronyl nitroxide cation radical,2-(...)..." Chemical Physics Letters. 195. 21-24 (1992)
[Publications] K.Awaga: "Ferromagnetic properties and crystal structures of pyridyl and pyridinium α-nitronyl nitroxides." Synthetic Metals. (1993)
[Publications] K.Awaga: "α-Nitronyl nitroxide cation radicals:Crystal engineering for the molecular based organic ferromagnetism." Molecular Crystals and Liquid Crystals. (1993)
[Publications] K.Awaga: "Crystal structure and electronic state of the organic ferromagnet,nitrophenyl α-nitronyl nitroxide radical." Molecular Crystals and Liquid Crystals. (1993)
[Publications] K.Awaga: "Photoelectron spectroscopic studies of an α-nitronyl nitroxide radical:Mechanism of ferromagnetic intermolecular interaction." Molecular Crystals and Liquid Crystals. (1993)

1992 Fiscal Year Annual Research Report

分子磁性発現とその機構

Principal Investigator

木下 實 東京大学, 物性研究所, 教授 (40011530)

Research Products

[Publications] M.Kinoshita: "Finding of bulk ferromagnetism in stable organic radical crystal." Materials Research Society Symposium Proceedings. 247. 429-432 (1992)

[Publications] Y.Nakazawa: "Low temperature magnetic properties of ferromagnetic organic radical,p-NPNN." Physical Review B. 46. 8906-8914 (1992)

[Publications] M.Takahashi: "Mean-field theory of quasi one-dimensional Heisenberg magnet γ-phase p-NPNN." Journal of the Physical Society of Japan. 61. 3745-3751 (1992)

[Publications] T.Sugano: "Ferromagnetic intermolecular interaction in an organic redical,3-quinolyl nitronyl nitroxide(3-QNNN)." Chemical Physics Letters. 200. 235-240 (1992)

[Publications] D.Shiomi: "Magnetic properties of an organic biradical,m-BNN:m-Phenylene bis(α-nitronyl nitroxide)." Journal of the Physical Society of Japan. 62. 289-300

[Publications] M.Kinoshita: "Bulk ferromagnetism of the crystal of the organic radical,p-NPNN." Synthetic Metals. (1993)

[Publications] D.Shiomi: "Novel magnetic interactions in organic polyradical crystals based on nitronyl nitroxide." Synthetic Metals. (1993)

[Publications] K.Nozawa: "Magnetic properties and crystal structures of some nitronyl nitroxide derivatives." Synthetic Metals. (1993)

[Publications] D.Shiomi: "Magnetic energy gap in the crystal of an organic bi-radical,m-BNN:m-Phenylene bis(α-nitronyl nitroxide)." Molecular Crystals and Liquid Crystals. (1993)

[Publications] M.Tamura: "Magnetic properties of phenyl nitronyl nitroxides." Molecular Crystals and Liquid Crystals. (1993)

[Publications] M.Kinoshita: "Ferromagnetism in organic radical crystal." Molecular Crystals and Liquid Crystals. (1993)

[Publications] L.P.Le: "Searching spontaneous magnetic order by μSR in an organic ferromagnet---β-phase p-NPNN." Chemical Physics Letters. (1993)

[Publications] R.Kato: "Proparation and physical properties of an alloyed (DMe-DCNQI)_2Cu with fully deuterated DMe-DCNQI(DMe-DCNQI=2,5-dimethyl-N,N'-dicyanoquinonediimine)." Solid State Communications. (1993)

[Publications] M.Matsushita: "Novel organic ions of high-spin states.II:Determination of the spin multiplicity of the ground state and 1H-ENDOR study of the monoanion of m-phenylenbis(phenylmethylene)" Journal of the American Chemical Society. 114. 7470-7475 (1992)

[Publications] M.Matsushita: "Novel organic ions of high-spin states.III:Determination of the spin multiplicity of the ground state and 1H-ENDOR study of the monocation of m-phenylenebis(...)." Bulletin of the Chemical Society of Japan. (1993)

[Publications] T.Kondo: "Trasnport and magnetic properties of incommensurate layer compounds (RES)_XVS_2(RE=Rare Earth)." Solid State Communications. 84. 999-1003 (1992)

[Publications] T.Ishii: "Electronic properties of gold trichloride-graphite intercalation compound(AuCl_3-GICs)." Solid State Communications. 84. 1055-1058 (1992)

[Publications] K.Suzuki: "Phase transitions and magnetic properties of an organic conductor (BEDT-TTF)_6Cu_2Br_6 with mixed valence Cu ions." Synthetic Metals. (1993)

[Publications] K.Suzuki: "Conduction mechanism and two-dimensional magnetism in incommensurate layered compounds (RES)xMS2(RE=Rare Earth metal,M=Ta,V)." Synthetic Metals. (1993)

[Publications] T.Enoki: "Solid state properties of charge transfer complexes of TTF derivatives with 3d-transition metal halides." Molecular Crystals and Liquid Crystals. (1993)

[Publications] A.Nakayama: "Magnetic properties of activated carbon fibers." Synthetic Metals. (1993)

[Publications] Y.Miura: "Molecular design,synthesis and magnetic characterization of poly(phenylacetylene) with π-toporegurated pendant nitronyl nitroxide radicals as models for..." Journal of the Polymer Society. 30. 956-966 (1992)

[Publications] Y.Teki: "Topology and spin alignment in a novel organic high-spin molecule,biphenyl-3,4'-bis(phenylmethylene),as studied by ESR and a generalized UHF Hubbard calculation." Journal of the American Chemical Society. (1993)

[Publications] Y.Teki: "Topology and spin alignment in organic high-spin molecules." Bulletin of Magnetic Resonance. 14. (1992)

[Publications] K.Furukawa: "Molecular design,synthesis,and electron spin resonance detection of a ground-state tridecet(S=6) hydrocarbon as a model for 2D organic ferro- and superpara-magnets." Bulletin of Magnetic Resonance. 15. (1993)

[Publications] T.Takui: "Organic high-spin state ENDOR/TRIPLE spectroscopy:Spin and molecular structural studies of models for organic ferro- and superpara-magnets." Bulletin of Magnetic Resonance. 15. (1993)

[Publications] Y.Teki: "Role of the spin correlation and weakly interacting model for the spin alignment in organic high-spin molecules." Molecular Crystals and Liquid Crystals. (1993)

[Publications] K.Sato: "Spin polarization effect in organic high-spin molecules as studied by single crystal ESR and 1H-ENDOR spectroscopies." Molecular Crystals and Liquid Crystals. (1993)

[Publications] K.Furukawa: "Molecular design,synthesis,and electron spin resonance detection of a ground-state tridecet(S=6) hydrocarbon as a model for 2D organic ferro- and superpara-magnets." Molecular Crystals and Liquid Crystals. (1993)

[Publications] Y.Teki: "Magnetic behavior of (N-arylthio)-2,4,6-triphenylanilino radical crystals." Molecular Crystals and Liquid Crystals. (1993)

[Publications] Y.Miura: "Synthesis of nitroxide polyradicals by catalytic polycondensation of 3,5-diethylbenzenes carrying nitroxide radicals with diiodobenzenes and their magnetic..." Molecular Crystals and Liquid Crystals. (1993)

[Publications] Y.Teki: "Novel organic ions of high-spin states." Molecular Crystals and Liquid Crystals. (1993)

[Publications] T.Takui: "Unusually large negative spin polarization of hetero-spin composite high-spin carbenes as models for purely organic ferrimagnets:Topological through-bond..." Molecular Crystals and Liquid Crystals. (1993)

[Publications] K.Awaga: "Ferromagnetic and antiferromagnetic intermolecular interactions in the two-dimensional triangular lattice of an α-nitronyl nitroxide cation radical,2-(...)..." Chemical Physics Letters. 195. 21-24 (1992)

[Publications] K.Awaga: "Ferromagnetic properties and crystal structures of pyridyl and pyridinium α-nitronyl nitroxides." Synthetic Metals. (1993)

[Publications] K.Awaga: "α-Nitronyl nitroxide cation radicals:Crystal engineering for the molecular based organic ferromagnetism." Molecular Crystals and Liquid Crystals. (1993)

[Publications] K.Awaga: "Crystal structure and electronic state of the organic ferromagnet,nitrophenyl α-nitronyl nitroxide radical." Molecular Crystals and Liquid Crystals. (1993)

[Publications] K.Awaga: "Photoelectron spectroscopic studies of an α-nitronyl nitroxide radical:Mechanism of ferromagnetic intermolecular interaction." Molecular Crystals and Liquid Crystals. (1993)

木下實東京大学, 物性研究所, 教授 (40011530)