Structural Determination of the Short-lived Species by Time-resolved Electron Diffraction.

通过时间分辨电子衍射测定短寿命物质的结构。

• 批准号: 62430003
• 负责人: KONAKA Shigehiro
• 金额: $ 7.23万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62430003/
• 关键词: Gas Electron Diffraction; Flash Lamp; Optical Mulitichannel Analyzer; Time Resolution; Flash-Photolysis; Short-Lived Species; T_1 State; Molecular Structure; 気体電子回折; 短寿命 化学種; フォトダイオ-ドアレイ; フォトダイオードアレイ; 電子線回折; マルチチャンネル測光

A new electron diffraction apparatus has been designed and constructed in order to study the molecular structures of short-lived species. In this apparatus, the diffracted electrons are transformed into photons by an NE102A plastic scintillator which is set at the position of a photographic plate for the conventional apparatus. A fixed r^2-sector is set in front of the plastic scintillator. The photons are collected on an optical multichannel analyzer (ca.700 channels) by an optical lens put outside the vacuum chamber. The optical multichannel analyzer has a gating system which can provide time resolution of up to 20 ns.On the other hand, the nozzle tube is made of quartz and surrounded by four Xe flash lamps (100 J/F max. and 1F/S max. pulse duration is Ca. 200 mus) in order that short-lived species such as radicals and electronically excited molecules can be made efficiently by means of the flash-photolysis of precursor molecules. Electronic circuits are designed so that the trigger pulse of the flash lamps and the gate pulse of the optical multichannel analyzer system are synchronized with some amount of delay.At the present stage, a preliminary test is being carried out to check the performance of the system. The diffraction patterns of CC1_4 and CS_2 have been recorded with good reproducibility.

为了研究短命物种的分子结构，设计并建造了一种新的电子衍射装置。在该装置中，衍射电子通过NE102A塑料闪烁体转化为光子，该闪烁体设置在传统装置的照相板的位置。在塑料闪烁体前面设置一个固定的r^2扇区。光子通过放置在真空室外部的光学透镜收集在光学多通道分析仪（约 700 个通道）上。光学多通道分析仪具有门控系统，可提供高达 20 ns 的时间分辨率。另一方面，喷嘴管由石英制成，周围有四个 Xe 闪光灯（最大 100 J/F 和 1F/S 最大脉冲持续时间为 Ca. 200 mus），以便通过前体的闪光光解有效地产生短寿命物质，例如自由基和电子激发分子。 分子。电子电路的设计使得闪光灯的触发脉冲和光学多道分析仪系统的门脉冲以一定的延迟同步。现阶段正在进行初步测试以检查系统的性能。 CC1_4 和 CS_2 的衍射图样已被记录，具有良好的重现性。