1992 Fiscal Year Annual Research Report

πトポロジー対称性を制御した有機高分子磁性体の巨視的磁性発現機構の基礎的解析

Research Project

Project/Area Number	04205115
Research Institution	Osaka City University
Principal Investigator	工位武治大阪市立大学, 理学部, 教授 (10117955)
Co-Investigator(Kenkyū-buntansha)	手木芳男大阪市立大学, 理学部, 助手 (00180068)
Keywords	有機磁性体 / 分子性磁性 / 有機高分子磁性体 / πトポロジー / ランダム磁性体 / スピングラス / ESR / ENDOR
Research Abstract	磁気的ヒステリシスに代表される巨視的な強磁性的振舞を顕わに示す磁性高分子は全て室温においても特異なESRスペクトルを示す。磁気特性を微視的立場から解明するには高感度高分解能のESR及びENDOR法を採用した。まず磁性高分子の代表例の一つとして、ピレンヤベンゼン環を骨格としトリアリールメチルラジカル基をスピンサイトにもつ縮合多核多環芳香族ポリマー(A)を採用した。ESR測定では,線幅の広い吸収の主成分はガウス型線形を示し,線幅の狭い成分はスピン濃度と繰返し数の増大とともにローレンツ型線形の寄与の増大を示した。このことは、分子間スピン交換相互作用の増加による寄与と解釈できる。ESRスペクトルの特異な温度変化(3K〜300℃:温度降下に伴う共鳴磁場の低磁場シフト)はランダム磁性体に固有の挙動に酷似しており強磁性の前段階ともいえる短距離秩序状態の一つであるスピングラス状態の形成を強く示唆する。低磁場シフトは、スピン濃度の増加に対しても観測された(P-HBA系)。そこで比較的短稜離のスピン秩序形成を仮定した高スピン集合系のスピン双極子相互作用を仮定したアプローチによって、線形及びシフトの解析を検討したが大きなシフト量を再現できなかった。ピレンノBA系の線幅の狭いESR吸収線について、水素核の無秩序配向状態の固体ENDOR測定を行いスペクトルシミュレーションを行った結果,主成分は4つ以上の繰返し数から成るオリゴマー(S=1/2)であると推定できた。ピレンノBA系についてはさらに有機溶媒に可容な成分について,液相の水素核ENDOR測定を行った。シミュレーションの結果,77個の水素核の組(超徴細結合定数=0.14〜1.4MHz)で再現でき,6個の繰返し数をもつオリゴマーまたは低分子オリゴマーの混合物であることがわかった。固体では,オリゴマーの複数スピンサイトの大部分は,反強磁性的に結合しS=1/2を与える。

Research Products

(12 results)

All Other

All Publications (12 results)

[Publications] Y.Miura: "Molecular Design,Synthesie and Magnetic Characterization of Poly(phenylacetylene)with π-Toporegulated Pendant Nitronyl radicals as Models for Organic Superpara -and Ferro-Magnets" J.Polym.Sci. 30. 956-966 (1992)
[Publications] M.Matsushita: "Novel Organic Ions High-Spin States II.:Determination of the Spin Multiplicity of the Ground State and ^1H-ENDOR Study of the Monoanion of m-Phenylenebis(phenylmethylene)" J.Am.Chem.Soc.114. 7470-7475 (1992)
[Publications] Y.Teki: "Topology and Spin Alignment in a Novel Organic High-Spin Molecule Bipheny1-3,4'-bis(phenylmethylene),as Studied by ESR and a generalized UHF Hubbard Calculation" J.Am.Chem.Soc.
[Publications] Y.Teki: "Topology and Spin Alignment Organic High-Spin Molecules" Bull.Magn.Reson.
[Publications] K.Furukawa: "Molecular Design, Synthesis, and Electron Spin Resonance Detection of a Ground-States Tridecet(S=6)Hydrocarbon as a Model for 2D Organic Ferro-and Superpara-Magnets" Bull.Magn.Reson.
[Publications] T.Takui: "Organic High-Spin State ENDOR/TRIPLE Spectroscopt: Spin and Molecular Structural Studies of Models for Organic Ferro-and Ferri-Magnets" Bull.Magn.Reson.
[Publications] Y.Teki: "Role of the Spin Correlation and weakly Interacting Model for the Spin Alignment Organic High-Spin Molecules" Mol.Cryst.Cryst.
[Publications] K.Sato: "Spin polarization Effect in Organic High-Spin Molecules,as Studied by Sing Crystal ESR and ^1H-ENDOR Spectroscopies" Mol.Cryst.Liq.Cryst.
[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" Mol.Cryst.Liq.Cryst.
[Publications] Y.Teki: "Magnetic Behavior of(N-arylthio)-2,4,6-triphenylanilino Radical Crystals" Mol.Cryst.Liq.Cryst.
[Publications] Y.Miura: "Syntheses of Nitroxide Polyradicals by the Catalytic Polycondensation of 3,5-Diethynylbenzenes Carrying Nitroxide Radicals with Diiodobenzenes and Their Magnetic Characterzation" Mol.Cryst.Liq.Cryst.
[Publications] Y.Teki: "Novel Organic Ions of High-Spin States" Mol.Cryst.Liq.Cryst.

1992 Fiscal Year Annual Research Report

πトポロジー対称性を制御した有機高分子磁性体の巨視的磁性発現機構の基礎的解析

Principal Investigator

工位 武治 大阪市立大学, 理学部, 教授 (10117955)

Research Products

[Publications] Y.Miura: "Molecular Design,Synthesie and Magnetic Characterization of Poly(phenylacetylene)with π-Toporegulated Pendant Nitronyl radicals as Models for Organic Superpara -and Ferro-Magnets" J.Polym.Sci. 30. 956-966 (1992)

[Publications] M.Matsushita: "Novel Organic Ions High-Spin States II.:Determination of the Spin Multiplicity of the Ground State and ^1H-ENDOR Study of the Monoanion of m-Phenylenebis(phenylmethylene)" J.Am.Chem.Soc.114. 7470-7475 (1992)

[Publications] Y.Teki: "Topology and Spin Alignment in a Novel Organic High-Spin Molecule Bipheny1-3,4'-bis(phenylmethylene),as Studied by ESR and a generalized UHF Hubbard Calculation" J.Am.Chem.Soc.

[Publications] Y.Teki: "Topology and Spin Alignment Organic High-Spin Molecules" Bull.Magn.Reson.

[Publications] K.Furukawa: "Molecular Design, Synthesis, and Electron Spin Resonance Detection of a Ground-States Tridecet(S=6)Hydrocarbon as a Model for 2D Organic Ferro-and Superpara-Magnets" Bull.Magn.Reson.

[Publications] T.Takui: "Organic High-Spin State ENDOR/TRIPLE Spectroscopt: Spin and Molecular Structural Studies of Models for Organic Ferro-and Ferri-Magnets" Bull.Magn.Reson.

[Publications] Y.Teki: "Role of the Spin Correlation and weakly Interacting Model for the Spin Alignment Organic High-Spin Molecules" Mol.Cryst.Cryst.

[Publications] K.Sato: "Spin polarization Effect in Organic High-Spin Molecules,as Studied by Sing Crystal ESR and ^1H-ENDOR Spectroscopies" Mol.Cryst.Liq.Cryst.

[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" Mol.Cryst.Liq.Cryst.

[Publications] Y.Teki: "Magnetic Behavior of(N-arylthio)-2,4,6-triphenylanilino Radical Crystals" Mol.Cryst.Liq.Cryst.

[Publications] Y.Miura: "Syntheses of Nitroxide Polyradicals by the Catalytic Polycondensation of 3,5-Diethynylbenzenes Carrying Nitroxide Radicals with Diiodobenzenes and Their Magnetic Characterzation" Mol.Cryst.Liq.Cryst.

[Publications] Y.Teki: "Novel Organic Ions of High-Spin States" Mol.Cryst.Liq.Cryst.

工位武治大阪市立大学, 理学部, 教授 (10117955)