Development and Application cf Bistability in Molecule-based Magnetic Mterials

分子磁性材料双稳态的开发与应用

• 批准号: 13304054
• 负责人: AWAGA Kunio
• 金额: $ 34.44万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13304054/
• 关键词: Molecular magnetism; Bistability; nanomagnet; Single Molecule Magnet; 双安定性; 分子磁性体; 有機ラジカル; 高スピン金属クラスター; 量子効果

The science and technology of spin electronic devices have attracted much interest. In this project, we developed molecule-based magnetic materials for future spintronics.1)Thiazyl radicals possess chemical stability and strong intermolecular interactions. We carried out a systematic study, namely, chemical syntheses, structural analyses, and physical measurements on this radical family, and discovered room-temperature magnetic bistability, photo-induced phase transition, organic ferromagnetism, etc.2)Development of molecular-/nano-magnets is a key issue for spintronics. Some of transition-metal cluster complexes exhibit a hysteresis loop on magnetization curve, so that they are called single molecule magnets(SMM). In this project, we performed chemical modifications on SMM, in order to elucidate the magneto-structural correlation and to control the classical and quantum magnetic relaxations. The magneto-structural correlation in SMM was revealed.We also developed synthesis of novel nanomagnets. We succeeded in uniform coating of polystyrene beads (O.D.300-1000 nm) with cobalt hydroxides, and obtained spherical hollow nanomagnets of fee Co and spinel Co_3O_4.

自旋电子器件的科学和技术引起了人们极大的兴趣。在本项目中，我们开发了用于未来自旋电子学的分子基磁性材料。1）噻唑基自由基具有化学稳定性和强的分子间相互作用。我们对这一自由基家族进行了系统的研究，即化学合成、结构分析和物理测量，发现了室温磁双稳、光致相变、有机铁磁性等。2）分子/纳米磁体的发展是自旋电子学的关键问题。某些过渡金属簇合物的磁化曲线具有磁滞回线，因此被称为单分子磁体（SMM）。在这个项目中，我们对SMM进行了化学修饰，以阐明磁结构相关性并控制经典和量子磁弛豫。揭示了SMM中的磁结构相关性，并发展了新型纳米磁体的合成。我们成功地将氢氧化钴均匀地包覆在聚苯乙烯微球（O.D.300-1000 nm）上，得到了球形空心纳米铁钴磁体和尖晶石型Co_3O_4磁体。

项目成果

Packing Motifs and Magneto-Structural Correlations in Crystal structures of Metallo-Tetrakis(1,2,5-thiadiazole)porphyrazine Series, TTDPzM (M=H_2,Fe, Co, Ni, Cu, Zn)

金属四(1,2,5-噻二唑)紫菜嗪系列TTDPzM (M=H_2,Fe,Co,Ni,Cu,Zn)晶体结构中的堆积基序和磁结构相关性

• 发表时间: 2004
• 期刊: Chem.Euro.J 10
• 作者: Y.Suzuki;M.Fujimori;H.Yoshikawa;K.Awaga
• 通讯作者: K.Awaga

K.Takeda, K.Awaga, T.Inabe, A.Yamaguchi, H.Ishimoto, T.Tomita, H.Mitamura, T.Goto, N.Mon, H.Nojiri: "Magnetic anisotropy, tunneling effects, high-frequency EPR, and molecular structure offast-relaxation species of Mn-12"Phys.Rev. B65. 094424 (2002)

K.Takeda、K.Awaga、T.Inabe、A.Yamaguchi、H.Ishimoto、T.Tomita、H.Mitamura、T.Goto、N.Mon、H.Nojiri：“磁各向异性、隧道效应、高频

T.Kubo, T.Goto, T.Koshiba, K.Takeda, K.Awaga: "Mn-55 NMR in Mn-12 acetate : Hyperfine interaction and magnetic relaxation of the cluster"Phys. Rev. B65. 224425 (2002)

T.Kubo、T.Goto、T.Koshiba、K.Takeda、K.Awaga：“Mn-12 醋酸盐中的 Mn-55 NMR：超精细相互作用和簇的磁弛豫”Phys。

Magnetic anisotropy, tunneling effects, high-frequency EPR, and niolecular structure of fast-relaxation species of Mn_<12>

Mn_<12>快弛豫物质的磁各向异性、隧道效应、高频EPR和纳米分子结构

• 发表时间: 2002
• 期刊: Phys.Rev.B 65
• 作者: K.Takeda;K.Awaga;T.Inabe;A.Yamaguchi;H.Ishimolo;T.Tomita;H.Mitamura;T.Goto;N.Mori;H.Nojiri
• 通讯作者: H.Nojiri

Room-temperature magnetic bistability in organic radical crystals: Paramagnetic-diamagnetic phase transition in 1,3,5-trithia-2,4,6-triazapentalenyl

• DOI: 10.1103/physrevb.65.064434
• 发表时间: 2002-02-01
• 期刊: PHYSICAL REVIEW B
• 影响因子: 3.7
• 作者: Fujita, W;Awaga, K;Okamoto, H
• 通讯作者: Okamoto, H