Dynamics of Gas-Phase Clusters as Studied by Tune-Resolved Photoelectron

调谐分辨光电子研究气相团簇动力学

基本信息

批准号：
09440210
负责人：
NAGATA Takashi
金额：
$ 7.49万
依托单位：
The University of Tokyo (1998-1999)Okazaki National Research Institutes (1997)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

One of the fundamental issues regarding the properties of clusters, aggregates of atoms or molecules in the gas phase, concerns the dynamics of energy dissipation among their enormous numbers of degrees of freedom. In the present study, we have investigated (1) the energy relaxation processes, (2) the isomerization processes and (3) photodissociation processes of negatively-charged molecular clusters in terms of their geometrical and electronic structures. The findings are summarized as follows :1. The time evolution of the photoelectron signal from an electronically-excited (CィイD26ィエD2FィイD26ィエD2)ィイD2nィエD2ィイD1-ィエD1 is probed by fs time-resolved photoelectron spectroscopy. The excited state is found to decay with a lifetime of 1.5 ps, which can be regarded as the time required for the energy disposal into a specific intermolecular vibrational mode in the cluster anions.2. The electronic structures of (C0ィイD22ィエD2)ィイD2nィエD2ィイD1-ィエD1, (CSィイD22ィエD2)ィイD2nィエD2ィイD1-ィエD1 and [(C0ィイD22ィエD2)ィイD2 … More nィエD2ROH]ィイD1-ィエD1 (R = H, CHィイD23ィエD2) are investigated by photoelectron spectroscopy combined with ab initio calculations, demonstrating the coexistence of isomers having different electronic structures. These "electronic isomers" are well described as [CィイD22ィエD2OィイD24ィエD2ィイD1-ィエD1・ROH(COィイD22ィエD2)ィイD2n-2ィエD2] and [C0ィイD22ィエD2ィイD1-ィエD1・ROH (COィイD22ィエD2)ィイD2n-1ィエD2]3. The photodepletion-photoelectron measurement has revealed the floppiness of the isomeric forms of [(C0ィイD22ィエD2) ィイD24ィエD2HィイD22ィエD2O]ィイD1-ィエD1 clusters : the cluster anions are fluctuating between two forms of isomers as [CィイD22ィエD2OィイD24ィエD2ィイD1-ィエD1・HィイD22ィエD2O (C0ィイD22ィエD2) ィイD22ィエD2] 【double arrow】 [C0ィイD22ィエD2ィイD1-ィエD1・HィイD22ィエD20(C0ィイD22ィエD2) ィイD23ィエD2] at their own temperatures.4. The photodissociation processes of gas-phase tri-iodide anion, IィイD23ィエD2ィイD1-ィエD1, along with its weakly bound clusters, IィイD23ィエD2ィイD1-ィエD1・M, are studied by a combination of an ion-beam technique with a time-of-flight (TOF) method. The experimental results obtained shows convincingly that a single solvent molecule can inhibit the more energy-demanding channel of the IィイD23ィエD2ィイD1-ィエD1 photofragmentation to a considerable extent, which opens up a possibility of controlling the IィイD23ィエD2ィイD1-ィエD1 photofragmentation process via stepwise microsolvation. Less

一个一个一个一个一个ossues logarding clusters sipters sipaties sipation sipation septies siperties在本研究中，我们已经调查了（1）能量放松过程，（2）异构化过程在其几何结构和电子结构方面，分子簇总结如下：1。 D1通过FS时间 - 固定的光电子光谱探测。 C0 II D22 YIE D2）II D2N YIER D2- YIE D1，（CS II D22 YIE D2）I D2N YIE D2-YIE D1和-IRI D1（R = H，CH，CH，CHI，CHI，CH，CH，CHEI D2）是调查的，与Abitio Comenulation相结合，具有不同电子结构的异构体的共存。和[C0 I D22 I D2 II D1 -IN D1 roH（CO-I D22 I D2）II D2N-1 YIE D2]（C0 II II D22 YIER D2）LEE D24 YI D22 YI D22 YIE D2O] II D1 D1 D1 D1 D1簇：簇阴离子在两个异构体的两个形成器之间波动，d1 -eie d1 hi d22 yie d2o（c0 ii d22 yie d2）ii d22 yier d2] [双箭头] b d22 yie d20（c0 yie d20 yie d20（c0 ii ii d23 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2 yie d2。 4。气相 - 碘化物的光解异位过程，II D23 D2 II D1 -I D1，以及II-D23 Yi D1-yie D1 d1 d1 d1 d1 d1 d1 d1 d1 d1 d1 d1 d1 d1 （TOF）获得的实验结果表明，对流的solecule可以抑制D23 D23 D2-I D1-ED D1光片的较高能量的渠道，从而开放了控制的可能性D1-yie D1光片段通过逐步微量溶液