Control of photodissociation reaction of fluoromethane molecules using deformation in core-excited state

利用核心激发态变形控制氟甲烷分子的光解反应

• 批准号: 16550015
• 负责人: YOSHIDA Hiroaki
• 金额: $ 2.05万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16550015/
• 关键词: fluoromethane; Core excitation; Time-of-flight mass analyzer; Momentum imaging method; Synchrotron radiation; photodissociation; Nitrogen; Auger decay; イオン対生成; 3フッ化メタン; 運動エネルギー放出

At first, a Wiley-McLarlen type time-of-flight (TOF) mass spectrometer equipped with a two-dimensional position-sensitive detector, which was composed of a delay-line-type anode and Microchannel plates, was designed and constructed. The apparatus was installed into a vacuum chamber in the horizontal direction. The chamber was mounted as an endstation of the soft x-ray beamline BL6 of HiSOR in Hiroshima University. Synchrotron radiation was dispersed by a high-resolution monochromator and introduced into the chamber. Performance of the apparatus was tested using nitrogen molecule (N_2). Fragment ions (N^+, N^<++>) were produced after a photoexcitation of the nitrogen Is electron of N_2 and detected by the two-dimensional detector. The observed image for the fragment ions on the detector shows a concentric shape. This is quite reasonable based on the axial-recoil approximation in photodissociation of core-excited linear molecules, in which dissociation is much faster than molecular rotation.Next, the momentum images of N^+ and N^<++> were obtained after the N1s->σ^* resonant excitation by measuring the TOF spectra and position images on the detector. The obtained initial momentum vector of the fragment ion in dissociation is strongly distributed toward the direction of the electric vector of the incident light due to the Σ->Σ transition. Thus, the performance of the apparatus was satisfied sufficiently.Finally, the decay dynamics of core-excited CHF_3 molecule was investigated in the C K-edge. The peak of the kinetic-energy distribution of H^+ moves to high-energy side with the increase in excitation energy. At the C1s->3p resonant excitation, the kinetic-energy distributions of H^+ for (H^+-F^+) and (H^+-C^+) move to high-energy side in comparison with those for (H^+-CF_2^+) and (H^+-CF^+).

首先，设计和构造的Wiley-mclarlen型飞行时间（TOF）质谱仪配备了二维位置敏感检测器，该检测器由延迟线型阳极和微通道平板组成。将设备安装到水平方向上的真空室中。该腔室被安装为广岛大学HISOR柔软的X射线光束线BL6的端站。高分辨率单色仪分散并引入腔室。使用氮分子（N_2）测试了设备的性能。在氮的光激发是N_2的电子并由二维检测器检测后，产生了片段离子（N^+，N^<++>）。检测器上片段离子的观察到的图像显示出同心形状。这是基于核心激发线性分子的光解离时的轴向回归近似值，其中解离比分子旋转快得多。接下来，在N1S->σ^*恢复性兴奋后通过测量the the the tof spectra promentra和Serivate contection cons of Spectrate contection cons Onsportra promenta和stimate cons Onsportra promenta和stimate cons Onsport persivate cons Onsportra和stimate of pemastra pysect contection n n^+和n^<++>的动量图像。由于σ->σ跃迁，分离中片段离子的初始动量矢量强烈分布在入射光的电向矢量方向上。这是充分满足设备的性能。在最后，在C k-gede中研究了核心兴奋的CHF_3分子的衰减动力学。随着兴奋能量的增加，H^+动力学分布的峰值移至高能侧。在C1S-> 3P共振兴奋中，与（H^+ - C^+）的H^+的动力学分布相比，与（H^+-CF_2^+）和（H^+）和（H^+-CF^+）相比，（H^+ - f^+）移至高能量侧。

项目成果

Performance of gas-phase photochemistry beamline BL6 at HiSOR

气相光化学光束线 BL6 在 HiSOR 上的性能

• 发表时间: 2005
• 期刊: Journal of Electron Spectroscopy and Related Phenomena 144-147
• 作者: S.Hashimoto;S.Yamashita;H.Yoshida
• 通讯作者: H.Yoshida

Performance of gas-phase photochemistry baseline BL6 at HiSOR

HiSOR 下气相光化学基线 BL6 的性能

• 发表时间: 2005
• 期刊: Journal of Electron Spectroscopy and Related Phenomena 144-147
• 作者: Y.Ogi;K.Tsukiyama;H.Yoshida
• 通讯作者: H.Yoshida

The lowest-energy spectator Auger band of the CH_3F molecule observed via F and Cls→σ^* excitation

通过 F 和 Cls→σ^* 激发观察到的 CH_3F 分子的最低能量观众俄歇带

• 发表时间: 2005
• 期刊: Chemical Physics Letters 413
• 作者: H.Ishida;B.Rahaman;S.Kashino;K.Ueda
• 通讯作者: K.Ueda

The lower-energy spectator Auger band of the CH_3F molecule observed via F and Cls→σ* excitation

通过 F 和 Cls→σ* 激发观察到的 CH_3F 分子的低能观众俄歇带

• 发表时间: 2005
• 期刊: Chemical Physics Letters 413
• 作者: M.Alvaro;B.Ferrer;H.Garcia;S.Hashimoto;M.Hiratsuka;T.Asahi;H.Masuhara;K.Ueda
• 通讯作者: K.Ueda