Electron Attachment Studies for CHCl3 Using Ion Mobility Spectrometry

The dissociative electron attachment process for CHCl3 at different electric field have been studied with nitrogen as drift and carrier gas using corona discharge ionization source ion mobility spectrometry （CD-IMS）. The corresponding electron attachment rate constants varied from 1.26×10-8 cm3/（molecules s） to 8.24×10-9 cm3/（molecules s） as the electric field changed from 200 V/cm to 500 V/cm. At a fixed electric field in the drift region, the attachment rate constants are also detected at different sample concentration. The ionmolecule reaction rate constants for the further reaction between Cl^- and CHCl3 are also detected, which indicates that the technique maybe becomes a new method to research the rate constants between ions and neural molecules. And the reaction rate constants between Cl- and CHCl3 are the first time detected using CD-IMS.

Dissociative Electron Attachment to 1,2-Dichlorobenzene using Mass Spectrometry with Phosphor Screen

Anion mass spectrometry is developed on the basis of our home-made anion velocity map imaging apparatus. The Cl^-; product efficiency curve for dissociative electron attachment to 1,2-dichlorobenzene is obtained from 0.2 to 8 eV, meanwhile the sliced images of this anion are recorded at 1.2 and 6.0 eV corresponding to two peak positions of the product efficiency curve.

Dissociative Electron Attachment to Carbon Dioxide

Our experimental progresses on the reaction dynamics of dissociative electron attachment(DEA)to carbon dioxide(CO2)are summarized in this review.First,we introduce some fundamentals about the DEA dynamics and provide an epitome about the DEAs to CO2.Second,the experimental technique developments are described,in particular,on the highresolution velocity map imaging apparatus in which we put a lot of efforts during the past two years.Third,our findings about the DEA dynamics of CO2 are surveyed and briefly compared with the others’work.At last,we give a perspective about the applications of the DEA studies and highlight the inspirations in the production of molecular oxygen on Mars and the catalytic transformations of CO2.

The Electronegativity Analysis of c-C_4F_8 as a Potential Insulation Substitute of SF_6

The density distributions related to gas electronegativity for c-C4Fs gas, including negative ion, electron number and electron energy densities in the discharge process, are derived theoretically in both plane-to-plane and point-to-plane electrode geometries. These calculations have been performed through the Boltzmann equation in the condition of a steady-state Townsend （SST） experiment and a fluid model in the condition of both uniform and non-uniform electric fields. The electronegativity coefficients a = n-/ne of c-C4Fs and SF6 are compared to further describe the electron affinity of c-C4Fs. The result shows that c-C4Fs represents an obvious electron-attachment performance in the discharge process. However, c-C4Fs still has much weaker gas electronegativity than SF6, whose electronegativity coefficient is lower than that of SF6 by at least three orders of magnitude.

Theoretical Study of Haloacetonitrile Anions： CH2XCN^- （X=F, Cl）

Haloacetonitrile anions CH2XCN- （X=F, Cl） were studied by HF-SCF, Becke3-LYP, and MP2 methods together with the Dunning＇s basis set aug-cc-PVTZ. The vertical electron attachments to the neutral are endothermic. The geometrically optimized CH2FCN^- is mainly a valence-bounded anion and CH2FCN→CH2CN＋F^- is a nonadiabatic dissociation. This theoretical study in good agreement with the experimental results shows that the Becke3-LYP method is reasonable in describing the electronic structures of anions and dissociative attachment dynamics, while significant differences between MP2 and Becke3-LYP results are shown for the dissociation potential curves of CH2ClCN→CH2CN＋Cl^-.