Magnetic Properties of New spin-Peierls-like Substances

新型自旋 Peierls 类物质的磁性

基本信息

批准号：
01540277
负责人：
TAKAGI Seishi
金额：
$ 1.09万
依托单位：
Kyushu Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01540277/
关键词：
Cyanine dye TCNQ complex Spin-Peierls transition Low dimensional magnet Spin dynamics スピン-パイエルス転移

项目摘要

Some new substances in which spin-Peierls transition seems to be observed were synthesized and their magnetic properties were investigated in two years from 1989 to 1990.(l) Preparation of high quality crystals of organic saltsSome (cyanine dye-TCNQ) organic complex salts of which magnetic properties suggest the presence of spin-Peierls transition were synthesized and their high quality single crystals were obtained.(2) Temperature dependence of magnetic spin-susceptibilityThe spin-susceptibility of some salts were measured as a function of temperature by Faraday method. Two of the salts show an anomaly at low temperatures. Though the susceptibility at high temperatures were well described by a model of one-dimensional magnet, it abruptly, decreases at low temperatures.(3) Electron spin resonance (ESR)A single absorption of ESR is observed in the single crystals of the salts. The linewidth of the absorption strongly depends on the temperature and the direction of applied magnetic field. The temperature dependence of the susceptibility suggests the presence of spinPeierls transition at a low temperature. However, no anomaly is observed in the ESR spectra near the temperature. It is not clear whether the abrupt decrease of the susceptibility results in so-called spin-Peierls transition.(4) PublicationsA part of this research have been published in J. Mag. Mag. Materials 90&91 (1990) 241 with the title "Magnetic Properties of an Organic Ion-Radical Salt : DETzNC-[TCNQ]_2".

1989年至1990年的两年时间里，合成了一些似乎可以观察到自旋-佩尔尔斯转变的新物质，并研究了它们的磁性能。（l）高质量有机盐晶体的制备一些（花青染料-TCNQ）有机络盐其磁性表明存在自旋-Peierls转变，并合成了它们的高质量单晶。(2)磁自旋磁化率的温度依赖性一些材料的自旋磁化率通过法拉第法测量盐作为温度的函数。其中两种盐在低温下表现出异常现象。尽管一维磁体模型很好地描述了高温下的磁化率，但在低温下磁化率突然降低。(3)电子自旋共振(ESR) 在盐的单晶中观察到ESR的单次吸收。吸收的线宽很大程度上取决于温度和施加磁场的方向。磁化率的温度依赖性表明在低温下存在自旋佩尔斯转变。然而，在接近该温度的ESR光谱中没有观察到异常。目前尚不清楚磁化率的突然降低是否会导致所谓的自旋-佩尔斯转变。(4) 出版物这项研究的一部分已发表在J. Mag。马格。材料 90&91 (1990) 241，标题为“有机离子自由基盐的磁性：DETzNC-[TCNQ]_2”。