Study of Spin-forbidden Ionization and Excitation via Inner-shell Excitation

自旋禁阻电离和内壳层激发激发的研究

基本信息

批准号：
15350017
负责人：
KOSUGI Nobuhiro
金额：
$ 9.86万
依托单位：
Institute for Molecular Science (2004-2005)Okazaki National Research Institutes (2003)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15350017/
关键词：
Soft X-ray Emission Spectroscopy Resonant Raman Scattering Resonant Photoelectron Spectroscopy Exchange Interaction Spin-orbit Interaction Molecular Solid Forbidden Transition Molecular Cluster 共鳴X線発光内殻励起スピン禁制

项目摘要

The spin-forbidden transitions become observable in addition to spin-allowed multiplets in the soft X-ray photoelectron spectra and soft X-ray emission spectra by tuning the photon energy to the inner-shell excitation as an intermediate state. In this research, resonant spectroscopy of photoelectron and photon emission was applied to reveal spin-forbidden valence ionized states and valence excited states. Theoretical and experimental approaches for such resonant spectroscopy were developed. Spin multiplets are produced due to exchange interaction ; therefore, multiplet interaction in open-shell molecules was especially studied in detail.In the theoretical approaches, an ab initio R-matrix/Multi Quantum Defect Theory (MQDT) method was newly developed to analyze systematically both the bound state below the ionization threshold and the continuum state above the threshold. This R-matrix/MQDT approach was applied to open-shell molecules such as NO and O_2. We successfully distinguished between characteristics of inner-shell excitation and of individual molecule. The theoretical approach to treat core-valence exchange interaction reasonably has been established in this work.In the experimental approaches, a new-type and next-generation soft X-ray emission spectrometer was developed. The present energy resolution was about 4,500. This resolution is the best in the world and is much higher than the previous best resolution. The CCD detection system was improved to detect soft X-rays emitted via C, N and O is excitation. The transmission grating system was also designed to detect soft X-rays emitted via C, N and O 1s excitation. The experimental approach to treat spin-forbidden valence excitation has been established in this work. In addition, it is revealed with a newly-developed cluster photoelectron apparatus that forbidden bands in a single molecular system are observable after molecular cluster formation.

通过将光子能量调整到作为中间态的内壳激发，除了在软 X 射线光电子能谱和软 X 射线发射光谱中允许自旋多重态之外，还可以观察到自旋禁止跃迁。在这项研究中，应用光电子和光子发射的共振光谱来揭示自旋禁阻价电离态和价激发态。开发了这种共振光谱的理论和实验方法。由于交换相互作用而产生自旋多重态；在理论方法上，新发展了从头计算R矩阵/多量子缺陷理论（MQDT）方法，系统地分析了电离阈值以下的束缚态和高于阈值的连续状态。这种 R 矩阵/MQDT 方法适用于开壳层分子，例如 NO 和 O_2。我们成功区分了内壳激发特征和单个分子的特征。本工作建立了合理处理核价交换相互作用的理论方法。在实验方法上，研制了新型、下一代软X射线发射光谱仪。目前的能量分辨率约为4,500。这个分辨率是世界上最好的，比之前的最佳分辨率要高很多。改进了 CCD 检测系统，可检测通过 C、N 和 O 激发发射的软 X 射线。透射光栅系统还设计用于检测通过 C、N 和 O 1s 激发发射的软 X 射线。这项工作建立了处理自旋禁态价激发的实验方法。此外，利用新开发的团簇光电子装置揭示了在分子团簇形成后可以观察到单分子系统中的禁带。