THE PHOTOIONIZATION OF NITROGEN DIOXIDE

1962 ◽  
Vol 40 (6) ◽  
pp. 1064-1067 ◽  
Author(s):  
D. C. Frost ◽  
D. Mak ◽  
C. A. McDowell
Keyword(s):  
Nitrogen Dioxide ◽  
Ionization Potential ◽  
Electron Impact ◽  
Impact Ionization ◽  
Threshold Energy ◽  
Ionization Efficiency ◽  
Efficiency Curve ◽  
Mass Spectrometric Technique ◽  
Measuring Techniques ◽  
First Ionization Potential

The ionization of nitrogen dioxide by photons has been studied using a photoionization mass spectrometric technique and also by the ordinary electron impact method. The photoionization results show a large variation in the relative ionization efficiency within the energy range 9–14 ev, and help to explain the differences between previously reported values for the first ionization potential of this compound. The photoionization efficiency curve indicates the first ionization potential to lie at 9.8 ev and inner ionization potentials to lie at about 11.1 and 12.7 ev.The electron impact ionization efficiency curve for the NO2+ ion exhibits a low ion intensity near the threshold. This confirms the viewpoint that previous determinations of the first ionization potential have employed threshold energy measuring techniques not properly suited for the type of molecule such as nitrogen dioxide which radically changes symmetry on ionization.

The 1650-1350 Å absorption spectrum of nitrogen dioxide

1962 ◽  
Vol 267 (1330) ◽  
pp. 395-407 ◽  
Keyword(s):  
Absorption Spectrum ◽  
Nitrogen Dioxide ◽  
Ionization Potential ◽  
Ground State ◽  
Band System ◽  
Anharmonic Constant ◽  
Rydberg Transitions ◽  
First Ionization Potential

An analysis of the 1650-1350 Å band system of nitrogen dioxide has been carried out. A pattern of band spacings and intensities is found that is complex but regular. It is shown that this pattern is qualitatively, and to a large extent quantitatively, just what would be expected for a transition in which the shape of the molecule changes from bent to linear. The transition is a parallel one and the upper state has 2 Σ + u symmetry. The symmetrical stretching frequency is increased from its ground-state value to ca. 1420 cm -1 in the upper state. The upper-state bending frequency is ca. 600 cm -1 . The N — O length is decreased from its groundstate value, probably to 1·1(3) Å. The upper state resembles closely the ground state of NO + 2 . The transition is to be classed as one of the Rydberg transitions leading to the first ionization potential of NO 2 ; and the orbital to which the odd electron is transferred in the transition is (pσ) in type. The anharmonic constant g 22 for the linear upper state is found to be 2·(3) cm -1 . Other Rydberg transitions may well be present in the region, but have not been definitely identified.

Energetics of the Ionization and Fragmentation of Phosphorus Trifluoride by Electron Impact

1975 ◽  
Vol 53 (6) ◽  
pp. 933-938 ◽  
Author(s):  
David F. Torgerson ◽  
John B. Westmore
Keyword(s):  
Mass Spectrum ◽  
Electron Impact ◽  
Ionization Efficiency ◽  
Negative Ion ◽  
Efficiency Curve ◽  
Group V ◽  
Fragmentation Pathways ◽  
Ion Fragmentation ◽  
Positive Ions ◽  
Significant Intensity

Relative intensities and appearance potentials of several positive ions in the mass spectrum of PF3 are reported as well as an ionization efficiency curve for F−, the only negative ion of significant intensity. Probable ion fragmentation pathways are proposed, together with heats of formation of some positive ions, and ionization potentials for PF3, PF2·, and PF. The results are compared with available data for other Group V halides.

Electron impact ionization efficiency curves of van der Waals clusters

1991 ◽  
Vol 2 (3) ◽  
pp. 183-201 ◽  
Author(s):  
Gopalakrishnan Vaidyanathan ◽  
M. Todd Coolbaugh ◽  
James F. Garvey
Keyword(s):  
Electron Impact ◽  
Impact Ionization ◽  
Van Der Waals ◽  
Electron Impact Ionization ◽  
Ionization Efficiency ◽  
Van Der Waals Clusters

Studies of the ionization of molecules by electron impact I. Excited states of the nitrogen molecular ion

1955 ◽  
Vol 232 (1189) ◽  
pp. 227-235 ◽  
Keyword(s):  
Electron Impact ◽  
Molecular Orbital ◽  
Excited States ◽  
Spectroscopic Data ◽  
Molecular Nitrogen ◽  
Nitrogen Molecule ◽  
Ionization Efficiency ◽  
Efficiency Curve ◽  
Pulse Technique ◽  
Good Agreement

A recently developed pulse technique which produces a beam of electrons with an energy spread of only 0·1 eV has been used to determine the ionization efficiency curve for molecular nitrogen in a mass spectrometer. Ionization to all four known excited states of the N + 2 ion, including the recently identified 2 π< u state, are clearly recognizable on the ionization efficiency curve. The several ionization potentials of the nitrogen molecule, as given by this new electron impact method, are in good agreement with the values deduced from spectroscopic data. The results are also shown to be in agreement with the expectations of the molecular orbital formula for nitrogen given some years ago by Mulliken (1932).

Electron impact ionization efficiency curves of argon clusters and argon/methanol heteroclusters

1992 ◽  
Vol 96 (4) ◽  
pp. 1589-1593 ◽  
Author(s):  
Gopalakrishnan Vaidyanathan ◽  
M. Todd Coolbaugh ◽  
James F. Garvey
Keyword(s):  
Electron Impact ◽  
Impact Ionization ◽  
Electron Impact Ionization ◽  
Ionization Efficiency ◽  
Argon Clusters

scholarly journals Numerical Simulations and the Design of Magnetic Field-Enhanced Electron Impact Ion Source with Hollow Cylinder Structure

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Guochen Qi ◽  
Di Tian ◽  
Guolun Gao ◽  
Guangda Liu ◽  
Chunling Qiu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electron Impact ◽  
Hollow Cylinder ◽  
Impact Ionization ◽  
Transmission Efficiency ◽  
Ion Source ◽  
Ionization Efficiency ◽  
Negative Ion ◽  
Ionization Source ◽  
Electron Intensity

An electron impact ion source-adopted magnetic field-enhanced technology has been designed for enhancing the electron intensity and the ionization efficiency. Based on the ion optic focus mechanism, an electron impact ionization source was designed, and the electron entrance into the ionization chamber was designed with a hollow cylinder structure to improve the ion extraction efficiency. Numerical simulation and optimal geometry were optimized by SIMION 8.0 to provide higher electron intensity and ion transmission efficiency. To improve the electron intensity, the influence of the filament potential and magnetic intensity was investigated, and the values of 70 eV and 150 Gs were chosen in our apparatus. Based on the optimal parameters, the air in the lab and oxygen gas was detected by the homemade apparatus, and the ion intensity was detected in the positive and negative ion modes, respectively. The homemade electron impact ion source apparatus has the potential to enhance ionization efficiency applied in the mass spectrometer ionization source.

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