Electron Scattering and Electron Angular Anisotropy in Water and Aqueous Solution

水和水溶液中的电子散射和电子角各向异性

• 批准号: 20K15229
• 负责人: THUERMER STEPHAN
• 金额: $ 2.66万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Early-Career Scientists
• 财政年份: 2020
• 资助国家: 日本
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-20K15229/
• 关键词: electron spectroscopy; electron scattering; liquid water; photoelectron anisotropy; aqueous solution; synchrotron radiation

The project gives new insights into electron scattering mechanisms in liquid water and aqueous solutions and its impact on photoelectron angular distributions using photoelectron spectroscopy in international collaboration. Electron scattering is crucial for understanding energy deposition, radical formation, and biological damage by slow and fast electrons, and a correct interpretation of spectra from liquid water and aqueous solutions.In the past year, it was demonstrated that surface-active molecules (here: perfluoropentanoate) in aqueous solution can be precisely mapped using photoelectron angular distributions (PADs). Electron scattering alters the PAD signature in a way that is uniquely linked to the probing depth down to an Angstrom resolution. Combined with the chemical specificity of photoemission, this novel technique paves the way to study the detailed surface composition of solutions relevant for, e.g., atmospheric chemistry.Recent results reveal that electron scattering affects surface-active species differently than bulk species. Photoelectrons from the surface do not suffer from scattering in the bulk liquid, and are thus detectable down to much lower kinetic energies. This distinction is crucial to understand photoelectron spectra from low-energy sources such as lasers, which might be misinterpreted if the surface-propensity and concentration is not considered. These results are currently prepared for publication.Furthermore, a method for accessing the work function (surface potential) of aqueous solutions has been developed and is currently under review.

该项目提供了新的见解，在液态水和水溶液中的电子散射机制及其对光电子角分布的影响，使用光电子能谱在国际合作。电子散射对于理解慢电子和快电子的能量沉积、自由基形成和生物损伤，以及正确解释液态水和水溶液的光谱至关重要。在过去的一年里，人们证明了水溶液中的表面活性分子（这里：全氟戊酸）可以使用光电子角分布（PAD）精确映射。电子散射改变PAD签名的方式，是唯一链接到探测深度下降到埃的分辨率。结合光电发射的化学特异性，这种新技术为研究与以下相关的溶液的详细表面组成铺平了道路，例如，最近的结果表明，电子散射对表面活性物质的影响不同于对本体物质的影响。来自表面的光电子在本体液体中不受散射的影响，因此可以检测到低得多的动能。这种区别对于理解来自低能量源（如激光）的光电子谱至关重要，如果不考虑表面倾向和浓度，则可能会被误解。这些结果目前正在准备出版。此外，已经开发出一种评估水溶液功函数（表面电位）的方法，目前正在审查中。

项目成果

Shake-up and shake-off satellites as a probe of ultrafast charge delocalization in liquid water

震动和抖落卫星作为液态水中超快电荷离域的探测器

• 发表时间: 2021
• 作者: 山本 桜路;星野 翔麻;築山 光一;Nishimoto Yoshio;Stephan Thuermer
• 通讯作者: Stephan Thuermer

Valence Photoelectron Spectra of Liquid Methanol and Ethanol Measured Using He II Radiation

使用 He II 辐射测量液体甲醇和乙醇的价光电子能谱

• DOI: 10.1021/acs.jpca.1c00288
• 发表时间: 2021
• 期刊: The Journal of Physical Chemistry A
• 作者: Thuermer Stephan;Shinno Takatoshi;Suzuki Toshinori
• 通讯作者: Suzuki Toshinori

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谷歌学术用户资料

How shake-up and shake-off satellites can reveal ultrafast charge delocalization in liquid water

抖落卫星如何揭示液态水中的超快电荷离域

• 发表时间: 2022
• 作者: Joe Komeda;Kenji Takada;Hiroaki Maeda;Naoya Fukui;Takuya Tsuji;Hiroshi Nishihara;Stephan Thuermer
• 通讯作者: Stephan Thuermer

Photoelectron Circular Dichroism from Aqueous-Phase Biomolecules

水相生物分子的光电子圆二色性

• 发表时间: 2023
• 作者: M. Pugini;D. Stemer;K. Mudryk;L. Tomanik;S. Malerz;F. Trinter;T. Buttersack;U. Hergenhahn;I. Wilkinson;S. Thuermer;P. Slavicek;B. Winter;G. Meijer
• 通讯作者: G. Meijer