CAUTERIZATION OF DIELECTRIC PROPERTIES FOR MONOLAYERATAIR-WATER INTERFACE BY MEANS OF MAXWELL DISPLACEMENT CURRENT AND OPTICAL SECOND HARMONIC GENERATION MEASURMENT

麦克斯韦位移电流和光学二次谐波产生测量单层空气-水界面介电性能

• 批准号: 12450122
• 负责人: IWAMOTO Mitsumasa
• 金额: $ 7.3万
• 依托单位: Tokyo Institute of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450122/
• 关键词: Maxwell Displacement Current; Second Harmonic Generation; Dielectric Phenomena; Order Parameter; Organic monolayer; Liquid crystal; Langmuir-Blodgett Films; Phase Transition

The purpose of this investigation was to characterize the linear and nonlinear dielectric properties of organic monolayer films by means of Maxwell-displacement current (MDC) and optical Second Harmonics Generation (SHG) measurement. The macroscopic dielectric properties such as linear and nonlinear dielectric constants are strongly related to the orientational order parameters of the constituent molecules. From this point of view, this investigation has been carried out on the basis of the idea of MDC measurement coupled with SHG measurement, proposed by the investigators.The investigators measured MDC and SHG signals from the monolayer on the water surface of nCB and nOCB molecules, where they constructed a new measurement system using 532 (and 1064 nm) fundamental waves to gain the high SN ratio. Using the experimental results, they clarified the relationship between MDC and photoisomerization of azo-molecules based on the quantum chemical three-state model Furthermore they analyzed the phase transition occurring in phospholipid and liquid crystal monolayers using a continuum elastic-theory. They detected this kind of phase transitions in nOCB liquid crystalline monolayer. Finally they derived the theoretical relationship between the microscopic and macroscopic nonlinear susceptibilities in C_2 symmetry.

本研究的目的是通过麦克斯韦位移电流（MDC）和光学二次谐波产生（SHG）测量来表征有机单层膜的线性和非线性介电性质。宏观介电性质如线性和非线性介电常数与组成分子的取向有序参数密切相关。从这一点出发，本研究基于本研究者提出的MDC测量与SHG测量相结合的思想，通过测量nCB和nOCB分子在水表面的单分子层的MDC和SHG信号，构建了一个利用532（和1064 nm）基波获得高信噪比的新测量系统。利用实验结果，他们基于量子化学三态模型阐明了MDC与偶氮分子光致异构化之间的关系，并利用连续弹性理论分析了磷脂和液晶单分子膜中发生的相变。他们在nOCB液晶单层中检测到了这种相变。最后导出了C_2对称性中微观与宏观非线性极化率之间的理论关系。

项目成果

Mitsumasa Iwamoto: "Electrical Properties of Organic Monolayer Films"Supramolecular Photosensitive and Electractive Materials (edited by H.S.Nalwa). 859-906 (2001)

Mitsumasa Iwamoto：“有机单层薄膜的电性能”超分子光敏和电材料（H.S.Nalwa 编辑）。

Yutaka Noguchi: "Space charge effect and the step voltages in metal/polyimide/rhodamine-dendorimer/polyimide/Metal junction"J. Appl. Phys.. 90. 1368-1370 (2001)

Yutaka Noguchi：“金属/聚酰亚胺/罗丹明树枝状聚合物/聚酰亚胺/金属结中的空间电荷效应和阶跃电压”J。

Atsushi Tojima: "Orientational order study of 4-alkyl-4-cyanobiphenyl Langmuir films by Maxwell displacement current and optical second harmonic generation measurements"Thin Solid Films. 393. 86-91 (2001)

Atsushi Tojima：“通过麦克斯韦位移电流和光学二次谐波产生测量对 4-烷基-4-氰基联苯朗缪尔薄膜进行取向顺序研究”薄膜固体。

Y. Miura, G. C. Xu, S. Kimura, S. Kobayashi, M. Iwamoto, Y. Imanishi, J. Umemura: "Multilayer formation of oriented helical peptides glued by hydrogen bonding"Thin Solid Films. 393. 59-65 (2001)

Y. Miura、G. C. Xu、S. Kimura、S. Kobayashi、M. Iwamoto、Y. Imanishi、J. Umemura：“氢键粘合定向螺旋肽的多层形成”固体薄膜。

Mitsumasa Iwamoto: "Generation of Maxwell Displacement Current Across Liquid Crystal Monolayers and Control of Liquid Crystal Alignment"Mol.Liquid.Cryst.Liquid. 347(invited). 65-79 (2000)

Mitsumasa Iwamoto：“跨液晶单层的麦克斯韦位移电流的产生和液晶排列的控制”Mol.Liquid.Cryst.Liquid。