Raman scattering study on organic semiconductors having gigantic dielectric constant

大介电常数有机半导体的拉曼散射研究

• 批准号: 01550007
• 负责人: IWASA Yoshihiro
• 金额: $ 1.54万
• 依托单位: Department of Applied Physics, University of Tokyo
• 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-01550007/
• 关键词: organic charge transfer compounds; gigantic dielectric constant; current switching effect; spin-Peierls phase; charge soliton dynamics; Raman scattering; infrared spectroscopy; 1次元性; 格子転移; 分子エレクトロニクス; 巨大誘電応答; ソリトンダイナミクス

Mixed stack organic semiconductors, composed of oneーdimensional chains of alternately stacked donor and acceptor molecules have an instability to molecular valence change. These materials show anomalous response to the electric field. One is a gigantic dielectric response and the other is a current switching effect. Especially, the latter has been attracted much attention in this decade due to possible application to molecular electronics. We have investigated the transport, dielectric, and optical properties of these materials. Raman and infrared spectra were measured to investigate the microscopic properties of the switch-on state.From the experimental results, we have concluded that the stacking fault on the one-dimensional chain (in other words, solitons) play important roles in the dynamical properties of these compounds. The ionic charge transfer compounds undergo a structural phase transition. The switching effect was found to occur conspicuously in the low temperature phase, where neighboring molecules are dimerized. It was found that this dimerization order is partially broken by too much current mediated by solitonic charge carriers.

混合堆栈有机半导体，由堆叠供体的一维链组成，受体分子具有不稳定的分子价变化。这些材料对电场表现出异常反应。一种是巨大的二元响应，另一种是当前的切换效果。尤其是，由于可能应用于分子电子产品，后者在这十年中引起了很多关注。我们已经研究了这些材料的运输，介电和光学性能。测量了拉曼和感染光谱以研究开关状态的显微镜特性。从实验结果，我们得出的结论是，一维链上的堆叠断层（换句话说，固体）在这些化合物的动态特性中起着重要作用。离子电荷转移化合物经历结构相变。发现开关效应在邻近分子二聚体的低温阶段明显出现。发现该二聚化顺序被孤子电荷载体介导的电流过多而部分打破。

项目成果

岩佐 義宏 国府 隆夫: ""有機電荷移動錯体におけるソリトン・ダイナミクス"" 固体物理.

Yoshihiro Iwasa 和 Takao Kokufu：“有机电荷转移复合物中的孤子动力学”固体物理学。

国府田 隆夫,岩佐 義宏: ""有機錯体結晶の相転移と非線形伝導"" 応用物理.

Takao Kouda、Yoshihiro Iwasa：“有机复合晶体中的相变和非线性传导”应用物理学。

Y.Iwasa, N.Watanabe, T.Koda, S.Koshihara, Y.Tokura, N.Iwasawa,and G.Saito.: "the Physics and Chemistry of Organic Superconductors" Springer Verlag Berlin,Heidelberg, 476 (1990)

Y.Iwasa、N.Watanabe、T.Koda、S.Koshihara、Y.Tokura、N.Iwasawa 和 G.Saito.：“有机超导体的物理和化学” Springer Verlag Berlin，海德堡，476 (1990)

H.Okamoto et al.: "Anomalous Dielectric response of a mixed-stack Charge Transfer Crystal:Tetrathiafulvalene-p-chloranil." to be published in Physical Review B.(1990)

H.Okamoto 等人：“混合堆电荷转移晶体的异常介电响应：四硫富瓦烯-对四氯苯醌”。

Y.Iwasa,I.Soga,T.Koda,Y.Tokura,and G.Saito.: "“Neutralーionic transition in TTFーchloranil and TMBーTCNQ."" Synth.Metals.

Y.Iwasa、I.Soga、T.Koda、Y.Tokura 和 G.Saito.：““TTF-四氯苯醌和 TMB-TCNQ 中的中性离子转变。”Synth.Metals。