Study on Molecular Dynamics near Solid-Liquid Interface by Evanescent Light Scattering Spectroscopy

倏逝光散射光谱研究固液界面附近的分子动力学

基本信息

批准号：
10450033
负责人：
TAKAGI Kenshiro
金额：
$ 9.47万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10450033/
关键词：
Evanescent light Light scattering Molecular dynamics near interface Diffusion of particles Frustrated total reflection Brownian motion 動的光散乱界面特異構造界面近傍粘性動的分子物性

项目摘要

Recently, various kinds of strange microstructures of molecular association formed near the liquid-solid interface attract great interests both in the physical and industrial fields. We developed a new technique of Dynamic Evanescent Light Scattering Spectroscopy to investigate the structure and dynamics of liquid materials in the vicinity of solid-liquid interface. Dynamic light scattering measurement has been an effective technique to study the molecular dynamics in liquids through the behavior of the thermal diffusion, phonons and Brownian motion excited by the thermal fluctuation. Evanescent light is the leaky optical wave generated in the vicinity of the interface at the total reflection condition. Since the penetration length of the evanescent light is in the order of several tens of nm, it would be an effective probe to pick up the information on the near-interface region. The purpose of this study is to establish the dynamic evanescent light scattering method as a powerful tool of investigating the interface physics of soft materials. We also aimed to study the physical interaction between the interface and molecules or molecular association from the microscopic viewpoint.As a result of the study we successfully developed two different light scattering measurement systems; one is the evanescent light scattering system and the other is the frustrated evanescent light scattering system. These two methods are different in their principles and give complementary information on the dynamics at the interface region. We revealed the diffusion behavior of the micro particles, which is suppressed by the hydrodynamic interaction from the solid wall. The experimental results ape well explained by the fluctuation dissipation the fluctuation dissipation theory taking the hydrodynamic effect into account. The Evanescent Light Scattering would be a powerful tool for the investigation of the strange structure of the soft complex materials near the interface.

近年来，液固界面附近形成的各种奇怪的分子缔合微观结构引起了物理和工业领域的极大兴趣。我们开发了一种动态倏逝光散射光谱新技术来研究固液界面附近液体材料的结构和动力学。动态光散射测量已成为通过热波动激发的热扩散、声子和布朗运动的行为来研究液体分子动力学的有效技术。倏逝光是在全反射条件下在界面附近产生的泄漏光波。由于倏逝光的穿透长度约为几十纳米，因此它将是获取近界面区域信息的有效探针。本研究的目的是建立动态倏逝光散射方法作为研究软材料界面物理的有力工具。我们还旨在从微观角度研究界面与分子或分子缔合之间的物理相互作用。作为研究的结果，我们成功开发了两种不同的光散射测量系统；一种是倏逝光散射系统，另一种是受抑倏逝光散射系统。这两种方法的原理不同，并且提供了有关界面区域动力学的互补信息。我们揭示了微粒的扩散行为，该行为受到固体壁的流体动力相互作用的抑制。实验结果很好地解释了考虑水动力效应的脉动耗散理论。倏逝光散射将成为研究界面附近软复杂材料的奇怪结构的有力工具。