Spectroscopy and dynamics on electron-ion recombination

气体、液体和固体中的电离现象一般由电子喷射开始，由产生的等离子体粒子（如电子和离子）碰撞维持，并由电荷清除反应（即正负离子或正离子与热化电子的复合）终止。随着气压的升高，在等离子体显示器或大气压臭氧发生器等各种应用中，电子-离子复合转变为电子和团簇离子。本研究的目的是发展一种新的光谱技术，并从超激发分子团簇在重组过程中产生的动力学角度来证实这一过程的动力学和动力学。为了实现这一目的，我们建立了一个新的质量选择团簇离子与单能电子的并束碰撞装置 ...更多信息 在高真空条件下。该装置由团簇离子束源、飞行时间质量选择器和余摆线电子谱仪组成。在团簇离子束源中，团簇离子是由中性团簇在超声膨胀中从脉冲气体喷嘴中通过电子碰撞电离产生的，并由脉冲电场提取。由此提取的团簇离子束被加速约5千伏，并通过1.2米的漂移管和质量选择使用飞行时间技术。我们已经证实了Ar_2和（CO_22）_2的质量选择团簇离子束<30><30>。采用束流合并技术将质量选择团簇离子束与单能电子束碰撞，在次摆线谱仪中将单能电子束的运动轨迹与质量选择团簇离子束合并，碰撞后与离子束分离。电子的能量色散和轨迹控制是同时进行的余摆线电子运动的原理下，电场和磁场都垂直于电子束。单能电子束的典型能量宽度为80 meV。通过测量Ar和CO_2的散射截面，验证了余摆线电子谱仪的性能，与文献报道的结果吻合较好。这样构造的电子-团簇离子复合装置是用于并束复合实验的最佳装置。少

Ionization phenomena in gases, liquids, and solids are generally initiated by the electron ejection, main-tained by the collisions of generated plasma particles, such as electrons and ions, and terminated by the charge clearing reaction, namely, recombination between positive and negative ions or that between positive ions and thermalized electrons. With the increase of pressure, where various applications, such as plasma display panel or atmospheric ozonizer, are developed, the electron-ion recombination changes into the for electrons and cluster ions. The purpose of the present investigation is to develop a new spectroscopic tech-que and to substantiate the dynamics and kinetics of the entitled process in such a phase from a point of view of the dynamics of superexcited molecular clusters temporally generated in recombination.In order to realize the present purpose, we have built a new apparatus for the merged-beams collision of mass selected cluster ions with mono-energetic electron … More s under the high vacuum condition. The apparatus consists of 1) cluster-ion beam source, 2) time-of-flight mass selector, and 3) trochoidal electron spectrometer. In the cluster-ion beam source, the cluster ions are generated by electron impact ionization of neutral clusters in supersonic expansion from a pulsed gas nozzle and extracted by a pulsed electric field. The cluster-ion beam thus extracted is accelerated by about 5 kV and travels through a 1.2 m drift tube and mass-selected using a time-of-flight technique. We have confirmed mass-selected cluster-ion beams up to Ar_<30> and (CO_22)_<30>. The mass-selected cluster ion beam is collided by a mono-energetic electron beam using a merged beams technique ; the trajectory of mono-energetic electron beam is merged with the mass-selected cluster-ion beam in the trochoidal spectrometer, and estranged from the ion beam after the collision. The energy dispersion of electrons and the control of trajectories are simultaneously carried out with the principle of trochoidal electron motion under an electric and magnetic fields both perpendicular to the electron beam. The typical energy width of mono-energetic electron beam is 80 meV.The performance of the trochoidal electron spectrometer is tested by obtaining the scattering cross sections for Ar and CO_2, which reasonably reproduce the published results. The apparatus for the electron-cluster ion recombination thus constructed is optimized for merged-beams recombination experiments. Less