A STUDY OF DESTRUCTION OF HIGHLY EXCITED MOLECULAR IONS PRODUCED IN THE EXTREME-ULTRAVIOLET REGION

极紫外区产生的高激发分子离子破坏的研究

• 批准号: 07640666
• 负责人: UKAI Masatoshi
• 金额: $ 1.47万
• 依托单位: Tokyo University of Agriculture and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07640666/
• 关键词: Molecular multiple excited states; Photoionization satellites; Synchrotron radiation; Mass spectrometry of fragment ions; Detection of neutral fragment fluorescence; Coincidence spectroscopy; Electron correlation; Nitrogen molecule

As well as the study of the multiply excited ionic states, i.e., the photoionization satellites, the study of molecular highly excited states excited by the photoabsorption of the energy above ca. 25 eV is quite improtant from the view point of the chemistry of highly excited molecules accompanying the electron correlation effect. The purpose of the present investigation has been to delope the spectroscopic method to identify and to observe the production and decay processes of such molecular highly excited states through the coincident measurments of the fragment photoions with the fluorescence from electronically excited neutral fragments. As shown below the purpose of the present investagation has been well accomplished.The present investigation has been carried out through the constructioin of the above mentioned experimental apparatus, nemely, a coincidence spectrometer, which is composed of a pulsed electromagnetic gas nozzle, a fluorescence detector, and a time-of-flight mass an … More alyzer and installed in a presently available highly evacuated vacuum chamber for collision of gas phase molecules with an extreme-ultraviolet photon beam. By developing, tuning, and using this apparatus, the investigation of entitled study has been performed for the tyipical diatomic molecules, such as hydrogen and nitrogen, by employing the monochromatized synchortron radiation at the Photon Factroy, the National Laboratory for High Energy Physics, Tsukuba.As for the results for nitrogen, the highly excited ions dissociating into a fragment ion (N^+) and an electronically excited neutral fragment (N^<**>) has been shown to correspond to the ions produced by the emission of electron from an inner valence orbital, with which almost no information was obtained previously. The detailed measurements of coincinent excitation funtin of fragment ions with fluorescence photons as a function of excitation photon energy have been performed. Also it has been successfully performed to reveal the production of ionic states with various symmetries the angular dependent coinicidence spectroscopy with respect to the polarization axis of synchrotron radiation. These have been the clear evidence showing the strong correlation between the one-electron ionic states and the multiply excited neutral molecules. Based on this rsult, the measurement of dispersed fluorescnce has been perfomed. It has been shown that a significant contribution of the fluorescence from ionic fragments is involved and that a certain molecular ionic state correlates to a certain fragment pair.As for the results for hydrogen, the coincidence spectra have shown that the one-electron ionic states with another one-electron excitetaion dissociate into a H^+ and a H^<**>, for which a detailed investigation has been performed by the measurements two dimensional coincidence spectroscopy. Further detailed information has been obtaine by the kinetic energy analysis of fragment ions using an electrostatic analyzer. Less

以及对多激发离子态的研究，即，光电离卫星，研究分子高激发态的光吸收激发的能量以上的CA。从伴随电子相关效应的高激发分子的化学观点来看，25 eV是相当重要的。本研究的目的是通过对碎片光离子与电激发中性碎片荧光的同步测量，发展光谱学方法来鉴别和观察这类分子高激发态的产生和衰变过程。本研究是通过建立上述实验装置，即由脉冲电磁气体喷嘴、荧光探测器和飞行时间质量计组成的符合谱仪来进行的。 ...更多信息 分析仪，并安装在目前可用的高度抽空的真空室中，用于气相分子与极紫外光子束的碰撞。通过研制、调试和使用该装置，在筑波高能物理国家实验室光子工厂，利用单色化同步加速器辐射，对典型的双原子分子如氢和氮进行了本课题的研究。高激发态离子解离成碎片离子（N^+）和电子激发态中性碎片（N^**>）已被证明对应于由电子从内价轨道发射而产生的离子，以前几乎没有获得任何信息。详细测量了碎片离子与荧光光子的重合激发函数随激发光子能量的变化。它也已成功地执行，以揭示各种对称性的离子态的产生角相关的同步辐射的偏振轴的重合光谱。这些都是单电子离子态与多激发态中性分子之间强相关的明显证据。在此基础上进行了色散荧光的测量。研究表明，离子碎片的荧光有显着贡献，并且某种分子离子态与某种碎片对相关。对于氢的结果，符合光谱表明，单电子离子态与另一个单电子激发态解离为H^+和H^<**>，通过测量二维符合光谱对其进行了详细的研究。通过静电分析仪对碎片离子进行动能分析，得到了更详细的信息。少

项目成果

M.Ukai: "Spectroscopy and dynamics of superexcited molecules as probed by the fluorescence measurements" Journal of Electron Spectroscopy. 79. 423-428 (1996)

M.Ukai：“通过荧光测量探测超激发分子的光谱学和动力学”《电子光谱学杂志》。

M.Ukai: "Dissociative photoionization of O_2 in the vuv region studied by photoion kinetic energy spectroscopy" Journal of Electron Spectroscopy. 79. 471-474 (1996)

M.Ukai：“通过光离子动能谱研究 vuv 区域中 O_2 的离解光电离”《电子能谱杂志》。

M.Kitajima: "Excitation function measurement of the dissociative photoionization excitation of nitrogen molecule utilizing the fluorescence photon-photoion coincidence technique" Atomic Collision Research in Japan. 21. 98-99 (1995)

M.Kitajima：“利用荧光光子-光离子符合技术测量氮分子的解离光电离激发的激发函数”日本原子碰撞研究。

M.Kitajima: "Excitation function measurement of the dissociative photoionization excitation of nitrogen molecule utilizing the fluorescence photon-photoion coincidence technique" Atomic Collision Research in Japan. ♯ 21. 98-99 (1995)

M.Kitajima：“利用荧光光子-光离子符合技术测量氮分子的解离光电离激发的激发函数”日本原子碰撞研究♯ 21. 98-99（1995）。

M.Ukai(分担): "Atomic and Molecular Photoionization" Universal Academy Press (Tokyo), 149-158 (1996)

M.Ukai（撰稿人）：“原子和分子光离子化”环球学院出版社（东京），149-158（1996）