Direct observation of molecular structure by Coulomb explosion imaging

库仑爆炸成像直接观察分子结构

基本信息

批准号：
11440178
负责人：
SHIROMARU Haruo
金额：
$ 9.6万
依托单位：
Tokyo Metropolitan University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

To establish the technique "Coulomb explosion imaging (CE1)", collision experiments of highly charged ions with various molecules were carried out. Dissociation of the multiply charged molecular ion was induced by the collision of Ar highly ionized beam extracted from an ECR ion source, and the trajectories of the fragments were derived from the values of the positions and the time-of-flights. The main results are as follows.1 : CEI was done by the detection of all fragments of linear triatomic molecules, CO_2 and CS_2, and nonlinear triatomic molecule, NO_2. The results were consistent with the known bond angles. The velocity vectors of the dissociating fragments were analyzed in detail by the change of charge and the collision energy. It was clarified that the charge states of the target molecule are the most critical factor governing dissociation process.2 : By GEI based oh the C-D-D triple coincidence measurement (detection of part of the fragments) of CD_4, it was shown that D-C-D bond angle was rightly obtained. This result indicates the possibility of the local structure analysis by CEI.3 : The chirality of CD_4, which was distorted by the zero point vibrations, was analyzed demonstrating that the CEI method can distinguish the molecular chirality directly.4 : The new position sensitive detector, which combined the resistance substrate with the backgammon type electrode, was developed. The performance was evaluated, and it was shown that very high position and time resolution were obtained.The above results were announced in the scientific journals as papers, as well as in domestic and foreign conferences. And, the test equipment for collision experiments of fullerenes with highly charged ions was manufactured in order to analyze the dissociation process of the fullerenes from the new standpoint, and the preliminary time-of-flight analysis experiment of the product was carried out.

为了建立“库仑爆炸成像（CE1）”技术，进行了高电荷离子的碰撞实验。通过从ECR离子源提取的AR高度离子梁的碰撞诱导了多电荷分子离子的解离，并且片段的轨迹源自位置的值和飞行时间。主要结果如下。1：CEI是通过检测所有线性三局分子（CO_2和CS_2）以及非线性triatomic Molecule的所有片段完成的，NO_2。结果与已知键角一致。通过电荷和碰撞能的变化详细分析了分离片段的速度向量。可以澄清的是，目标分子的电荷状态是控制解离过程的最关键因素。2：基于GEI的OH OH CD_4的C-D-D三重重合测量（检测部分片段的检测），证明D-C-D键角是正确获得的。该结果表明通过CEI进行局部结构分析的可能性。3：CD_4的手性（因零点振动而扭曲）进行了分析，表明CEI方法可以直接区分分子手性4：新的位置敏感检测器，将电阻式底物与背峰式电极结合了电极类型的电极。对性能进行了评估，并表明获得了很高的位置和时间分辨率。上述结果在科学期刊上宣布为论文以及家庭和外国会议。并且，制造了用于高电荷离子碰撞实验的测试设备，以便从新的角度分析富勒烯的解离过程，并进行了产品的初步飞行时间分析实验。